#!/bin/sh # # Copyright 2011 # Kaz Kylheku # Vancouver, Canada # All rights reserved. # # BSD License: # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions # are met: # # 1. Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # 2. Redistributions in binary form must reproduce the above copyright # notice, this list of conditions and the following disclaimer in # the documentation and/or other materials provided with the # distribution. # 3. The name of the author may not be used to endorse or promote # products derived from this software without specific prior # written permission. # # THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR # IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED # WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. # # Save command line in a way that can be re-run. # This takes care of spaces, but if there are shell-meta characters # in the arguments, oops. # set -u cmdline= for arg in "$0" ${@+"$@"} ; do [ -n "$cmdline" ] && cmdline="$cmdline " case $arg in *" "* | " "* | *" " ) cmdline=$cmdline$(printf "\"%s\"" "$arg") ;; * ) cmdline=$cmdline$arg ;; esac done # # Establish default values for any variables that are not specified # on the command line. The default derivations from prefix are in # Make syntax. They go verbatim into the generated config.make. # This way they can be overridden more flexibly at make time. # # # non-config # help= # # config # prefix=/usr/local install_prefix= bindir='$(prefix)/bin' datadir='$(prefix)/share/txr' mandir='$(prefix)/share/man' make= cross= compiler_prefix= ccname=gcc cc='$(cross)$(compiler_prefix)$(ccname)' intptr= tool_prefix= lex='$(cross)$(tool_prefix)flex' lexlib=-lfl yaccname_given= yaccname= yacc='$(cross)$(tool_prefix)$(yaccname)' yacc_given= nm='$(cross)$(tool_prefix)nm' opt_flags=-O2 lang_flags='--ansi -D_XOPEN_SOURCE=2' diag_flags='-Wall -Wmissing-prototypes -Wstrict-prototypes' debug_flags=-g inline= platform_flags= remove_flags= lex_dbg_flags= txr_dbg_opts=--gc-debug valgrind= lit_align= extra_debugging= debug_support=y gen_gc= mpi_version=1.8.6 have_quilt= have_patch= # # Parse configuration variables # while [ $# -gt 0 ] ; do case $1 in --no-* | --no_* ) var=${1#--no?} val= ;; --*=* ) var=${1%%=*} var=${var#--} val=${1#*=} ;; --*= ) var=${1%%=*} var=${var#--} val= ;; --* ) var=${1#--} val=y ;; *=* ) var=${1%%=*} val=${1#*=} ;; *= ) var=${1%%=*} val= ;; * ) printf "$0: '$1' doesn't look like a configuration variable assignment\n" printf "$0: use --help to get help\n" exit 1 esac var=$(echo "$var" | tr - _) if ! echo $var | grep -q -E '^[A-Za-z_][A-Za-z0-9_]*$' ; then printf "$0: '$var' isn't a proper configuration variable name\n" exit 1 fi eval "var_exists=\${$var+y}" if [ "$var_exists" != y ] ; then printf "$0: nonexistent option: '%s'\n" "$1" exit 1 fi eval "$var='$val'" eval "var_given_exists=\${${var}_given+y}" if [ "$var_given_exists" = y ] ; then eval "${var}_given=y" fi shift done # # If --help was given (or --help= or help=) then # print help and exit. The termination status is failed, to indicate # that configuration was not done. # if [ -n "$help" ] ; then cat < /dev/null) || true set -- $output printf "\$@=<$1> <$2> <$3>\n" if [ $1 != "GNU" -o $2 != "Make" ] ; then continue fi break done fi if [ -z "$make" ] ; then printf "missing\n" exit 1 fi make_version=$3 save_ifs=$IFS ; IFS=. ; set -- $make_version ; IFS=$save_ifs if [ $1 -lt 3 -o $ $1 -eq 3 -a $2 -lt 80 $ ] ; then printf "too old (%s found, 3.80 or newer needed)\n" $make_version exit 1 else printf "yes (%s found)\n" $make_version fi # # Verify sanity of --prefix and other directories. # printf "Checking installation paths:\n" for name in prefix bindir datadir mandir; do eval path="\$install_prefix\${$name}" printf "\$(install_prefix)\$(%s)=%s ... " $name "$path" test_access=y case "$path" in " "* | *" "* | *" " ) printf "incorrect (contains spaces)\n" exit 1 ;; -* ) printf "incorrect (resembles a command option)\n" exit 1 ;; *'$('* ) # It's a make expression; can't test it test_access= ;; /* ) ;; * ) printf "incorrect (must be absolute path)\n" exit 1 ;; esac if [ $test_access ] ; then test_prefix=$path while true ; do if [ -e $test_prefix ] ; then if [ ! -d $test_prefix ] ; then printf "incorrect ('%s' is not a directory)!\n" $test_prefix exit 1 fi if [ ! -w $test_prefix ] ; then printf "okay\n (but no write access to '%s'\n" $test_prefix printf " so '$make install' will require root privileges)\n" else printf "okay\n" fi break fi test_prefix=$(dirname $test_prefix) done else printf "okay\n (make variable derivation)\n" fi done # # First, we have to figure out whether we are configured straight # in the source directory, or whether we are in a separate build directory. # In the latter case, we set up a symbolic link to the Makefile. # source_dir="$(dirname $0)" # # Compute an absolute path to the source directory. # top_srcdir="$(cd "$source_dir" ; pwd -P)" printf "Checking source directory %s ..." "$top_srcdir" case "$top_srcdir" in " "* | *" "* | *" " ) printf " bad (contains spaces)\n" exit 1 ;; * ) printf " okay\n" ;; esac if [ "$source_dir" != "." ] ; then printf "Symlinking Makefile -> $source_dir/Makefile\n" ln -sf "$source_dir/Makefile" . else printf "Warning: its recommended to build in a separate directory\n" fi gen_config_make() { cat > config.make < config.h /* * Header file automatically generated by $0. * Tweaking this file may seem like a good temporary workaround * than tweak the file, but you probably should fix the script * to do the job. In any case, be aware that you will lose your * changes if you re-run $0. */ ! # # Check C compiler sanity # printf "Checking whether your C compiler can make a simple executable ... " cat > conftest.c < int main(void) { printf("Hello, world!\n"); return 0; } ! rm -f conftest if ! $make conftest > conftest.err 2>&1 || ! [ -x conftest ] ; then printf "failed\n\n" printf "Errors from compilation: \n\n" cat conftest.err exit 1 fi rm -f conftest printf "okay\n" # # Check for annoying clashes from non-conforming BSD-derived systems that don't # honor Unix/POSIX feature selection macros! # printf "Checking for name clashes caused by nonconforming toolchains ... " for ident in trunc floorf random longlong_t ; do cat > conftest.c < #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include struct txr_foo { int txr; } $ident; int $ident(void); int main(void) { return 0; } ! rm -f conftest if ! $make conftest > conftest.err 2>&1 || ! [ -x conftest ] ; then printf "#define %s txr_%s\n" $ident $ident >> config.h fi done printf "done\n" # # Check for annoying warnings from ctype.h macros # printf "Checking for annoying warnings from macros ... " cat > conftest.c < int main(void) { char x = '3'; return isdigit(x); } ! if ! $make EXTRA_FLAGS=-Werror conftest > conftest.err 2>&1 || ! [ -x conftest ] ; then printf "present\n" cat >> config.h < conftest.c < conftest.err 2>&1 ; then longlong=$try_type break fi done if [ -n "$longlong" ] ; then printf '"%s"\n' "$longlong" printf "#define HAVE_LONGLONG_T 1\n" >> config.h printf "typedef $longlong longlong_t;\n" >> config.h else printf "none\n" fi printf "Checking what C type we have for unsigned integers wider than \"long\" ... " ulonglong= for try_type in uint64 __uint64 "unsigned long long" ; do cat > conftest.c < conftest.err 2>&1 ; then ulonglong=$try_type break fi done if [ -n "$ulonglong" ] ; then printf '"%s"\n' "$ulonglong" printf "#define HAVE_ULONGLONG_T 1\n" >> config.h printf "typedef $ulonglong ulonglong_t;\n" >> config.h else printf "none\n" fi printf "Checking what C type we have for integers wider than \"long long\" ... " broken128= output=$($make conftest.ccver) set -- $output if [ "$1" = "gcc" ] ; then gcc_version=$3 save_ifs=$IFS ; IFS=. ; set -- $gcc_version ; IFS=$save_ifs if [ $1 -lt 4 ] || [ $1 -eq 4 -a $2 -le 3 ] ; then broken128=y fi fi superlong= if [ -z "$broken128" ] ; then for try_type in int128 int128_t __int128 __int128_t ; do cat > conftest.c < conftest.err 2>&1 ; then superlong=$try_type break fi done fi if [ -n "$superlong" ] ; then printf '"%s"\n' "$superlong" printf "#define HAVE_SUPERLONG_T 1\n" >> config.h printf "typedef $superlong superlong_t;\n" >> config.h else printf "none\n" fi printf "Checking what C type we have for u. integers wider than \"long long\" ... " usuperlong= if [ -z "$broken128" ] ; then for try_type in uint128 uint128_t __uint128 __uint128_t ; do cat > conftest.c < conftest.err 2>&1 ; then usuperlong=$try_type break fi done fi if [ -n "$usuperlong" ] ; then printf '"%s"\n' "$usuperlong" printf "#define HAVE_USUPERLONG_T 1\n" >> config.h printf "typedef $usuperlong usuperlong_t;\n" >> config.h else printf "none\n" fi printf "Checking what C integer type can hold a pointer ... " read_syms() { print_into_config=${1-} deferred_offset= while read symbol type offset size ; do size=$(( 0$size + 0 )) offset=$(( 0$offset + 0 )) symbol=${symbol#_} case "$type" in C ) size=$(( offset + 0 )) ;; S ) if [ -n "$deferred_offset" ] ; then size=$(( offset - deferred_offset )) case "$deferred_sym" in SIZEOF* ) eval $(printf "%s=%d\n" "$deferred_sym" "$size") if [ -n "$print_into_config" ] ; then printf "#define %s %s\n" "$deferred_sym" "$size" >> config.h fi ;; esac fi deferred_sym=$symbol deferred_offset=$offset continue ;; esac case "$symbol" in SIZEOF* ) eval $(printf "%s=%d\n" "$symbol" "$size") if [ -n "$print_into_config" ] ; then printf "#define %s %s\n" "$symbol" "$size" >> config.h fi ;; esac done < conftest.syms } if [ -z "$intptr" ] ; then cat > conftest.c < conftest.err 2>&1 ; then printf "failed\n\n" printf "Errors from compilation: \n\n" cat conftest.err exit 1 fi SIZEOF_PTR=0 SIZEOF_SHORT=0 SIZEOF_INT=0 SIZEOF_LONG=0 SIZEOF_LONGLONG_T=0 SIZEOF_SUPERLONG_T=0 read_syms y rm -f conftest.syms conftest.o if [ $SIZEOF_PTR -eq 0 ] ; then printf "failed\n" exit 1 fi if [ $SIZEOF_PTR -eq $SIZEOF_SHORT ] ; then intptr="short" uintptr=y elif [ $SIZEOF_PTR -eq $SIZEOF_INT ] ; then intptr="int" uintptr=y elif [ $SIZEOF_PTR -eq $SIZEOF_LONG ] ; then intptr="long" uintptr=y elif [ $SIZEOF_PTR -eq $SIZEOF_LONG_LONG_T ] ; then intptr="longlong_t" uintptr=$ulonglong fi if [ -z "$intptr" ] ; then printf "failed\n" exit 1 fi fi printf '"%s"\n' "$intptr" printf "typedef $intptr int_ptr_t;\n" >> config.h if [ -n "$uintptr" ] ; then printf "#define HAVE_UINTPTR_T 1\n" >> config.h printf "typedef unsigned $intptr uint_ptr_t;\n" >> config.h fi intptr_max_expr="((((($intptr) 1 << $((SIZEOF_PTR * 8 - 2))) - 1) << 1) + 1)" printf "#define INT_PTR_MAX %s\n" "$intptr_max_expr" >> config.h printf "#define INT_PTR_MIN (-INT_PTR_MAX)\n" >> config.h if [ -n "$longlong" ] && [ $SIZEOF_LONGLONG_T -eq $(( 2 * $SIZEOF_PTR )) ] then printf "#define HAVE_DOUBLE_INTPTR_T 1\n" >> config.h printf "typedef longlong_t double_intptr_t;\n" >> config.h elif [ -n "$superlong" ] && [ $SIZEOF_SUPERLONG_T -eq $(( 2 * $SIZEOF_PTR )) ] then printf "#define HAVE_DOUBLE_INTPTR_T 1\n" >> config.h printf "typedef superlong_t double_intptr_t;\n" >> config.h fi #if HAVE_LONGLONG_T && # # Alignment of wchar_t # # What we really want to know is the alignment of wide string literals # like L"wide literal". # # We make pessimistic assumption that the size of the wchar_t type is this # alignment. # # There is no easy way to get the information without running a compiled # program. # printf "Conservatively guessing the alignment of wide literals ... " if [ -z "$lit_align" ] ; then cat > conftest.c < char SIZEOF_WCHAR_T[sizeof (wchar_t)]; char DUMMY; ! rm -f conftest.o conftest.syms if ! $make conftest.syms > conftest.err 2>&1 ; then printf "failed\n\n" printf "Errors from compilation: \n\n" cat conftest.err exit 1 fi SIZEOF_WCHAR_T=0 deferred_offset= read_syms rm -f conftest.syms conftest.o if [ $SIZEOF_WCHAR_T -eq 0 ] ; then printf "failed\n" exit 1 fi lit_align=$SIZEOF_WCHAR_T fi printf "%d\n" "$lit_align" printf "#define LIT_ALIGN %d\n" "$lit_align" >> config.h # # Inline functions # printf "Checking how to declare inline functions ... " if [ -z "$inline" ] ; then for inline in \ "inline" "static inline" "extern inline" \ "__inline__" "static __inline__" "extern __inline__" \ "static" do cat > conftest1.c < conftest2.c < conftest.err 2>&1 ; then continue fi break done fi printf '"%s"\n' "$inline" printf "#define INLINE $inline\n" >> config.h # # Valgrind # if [ -n "$valgrind" ] ; then printf "Checking valgrind API availability ... " cat > conftest.c < #ifdef VALGRIND_DO_CLIENT_REQUEST int main(void) { return 0; } #else syntax error #endif ! rm -rf conftest if ! $make conftest > conftest.err 2>&1 || ! [ -x conftest ] ; then printf "failed\n\n" printf "Errors from compilation: \n\n" cat conftest.err exit 1 fi printf "okay\n" printf "#define HAVE_VALGRIND\n" >> config.h fi # # Yacc tests # printf "Checking for yacc program ... " if [ -z "$yacc_given" -a -z "$yaccname_given" ] ; then rm -f conftest.yacc for yaccname in "yacc" "byacc" "bison -y" "" ; do yaccpath=$($make yaccname="$yaccname" conftest.yacc) if command -v $yaccpath > /dev/null ; then break; fi done if [ -z "$yaccname" ] ; then printf "not found\n" exit 1 fi printf '"%s"\n' "$yaccpath" else yaccpath=$($make conftest.yacc) case $yaccpath in *bison ) printf "error\n\n" printf "GNU Bison needs -y to behave like yacc\n\n" printf "This needs to be specified in the --yaccname or --yacc option\n\n" exit 1 ;; * ) if ! command -v $yaccpath > /dev/null ; then printf "not found\n\n" exit 1 fi printf "given\n" ;; esac fi # # sys/wait.h # printf "Checking whether we have ... " cat > conftest.c < int main(void) { return 0; } ! rm -f conftest if ! $make conftest > conftest.err 2>&1 || ! [ -x conftest ] ; then printf "no\n" else printf "yes\n" printf "#define HAVE_SYS_WAIT 1\n" >> config.h fi # # sys/stat.h # printf "Checking whether we have ... " cat > conftest.c < int main(void) { struct stat s; return 0; } ! rm -f conftest if ! $make conftest > conftest.err 2>&1 || ! [ -x conftest ] ; then printf "no\n" else printf "yes\n" printf "#define HAVE_SYS_STAT 1\n" >> config.h fi # # environ # printf "Checking whether we have environ ... " cat > conftest.c < int main(void) { extern char **environ; puts(environ[0]); return 0; } ! rm -f conftest if ! $make conftest > conftest.err 2>&1 || ! [ -x conftest ] ; then printf "no\n" else printf "yes\n" printf "#define HAVE_ENVIRON 1\n" >> config.h fi # # GetEnvironmentStrings # printf "Checking whether we have GetEnvironmentStrings ... " cat > conftest.c < int main(void) { WCHAR *ptr = GetEnvironmentStringsW(); return 0; } ! rm -f conftest if ! $make conftest > conftest.err 2>&1 || ! [ -x conftest ] ; then printf "no\n" else printf "yes\n" printf "#define HAVE_GETENVIRONMENTSTRINGS 1\n" >> config.h fi # # fork, pipe, exec, waitpid. # printf "Checking for POSIX fork/pipe/exec/waitpid ... " cat > conftest.c < #endif #include int main(int argc, char **argv) { int status, fd[2]; pid_t p = fork(); (void) execvp(argv[0], argv); (void) waitpid(p, &status, 0); (void) pipe(fd); return 0; } ! rm -f conftest if ! $make conftest > conftest.err 2>&1 || ! [ -x conftest ] ; then printf "no\n" else printf "yes\n" printf "#define HAVE_FORK_STUFF 1\n" >> config.h fi # # Check for fields inside struct tm # printf "Printf detecting timezone fields in struct tm ..." tm_gmtoff= tm_tmzone= for try_field in tm_gmtoff __tm_gmtoff ; do cat > conftest.c < int x = sizeof ((struct tm *) 0)->$try_field; ! rm -f conftest.o if $make conftest.o > conftest.err 2>&1 ; then printf "#define HAVE_TM_GMTOFF 1\n" >> config.h printf "#define TM_GMTOFF %s\n" $try_field >> config.h break fi done for try_field in tm_zone __tm_zone ; do cat > conftest.c < int x = sizeof ((struct tm *) 0)->$try_field; ! rm -f conftest.o if $make conftest.o > conftest.err 2>&1 ; then printf "#define HAVE_TM_ZONE 1\n" >> config.h printf "#define TM_ZONE %s\n" $try_field >> config.h break fi done printf "done\n" # # Extra debugging. # if [ -n "$extra_debugging" ] ; then printf "Configuring extra debugging, as requested ...\n" printf "#define EXTRA_DEBUGGING 1\n" >> config.h fi # # Clean up # rm -f conftest conftest.[co] conftest.{err,syms} rm -f conftest2 conftest[12].[oc] # # What do we have for patch management. # printf "Checking for quilt ... " if ! quilt --version > /dev/null 2>&1 ; then printf "not found\n" else printf "found\n" have_quilt=y fi printf "Checking for patch ... " if ! patch --version > /dev/null 2>&1 ; then printf "not found\n" printf "\npatch tool required!\n\n" exit 1 else printf "found\n" have_patch=y fi # # Function to apply patches. # apply_patches() { if ! [ -e patches/series ] ; then echo "no patches" return 0 fi while read patch patchlevel ; do case patch in '#' ) continue ;; * ) patch ${patchlevel:--p1} < patches/$patch ;; esac done < patches/series } # # Try to extract MPI if not already. # printf "Extracting MPI ... " if [ -e mpi-${mpi_version} ] ; then printf "already extracted\n" else tar -xzf $top_srcdir/mpi-${mpi_version}.tar.gz printf "\n" printf "Symlinking MPI patches ...\n" ln -sf $top_srcdir/mpi-patches mpi-${mpi_version}/patches printf "Applying MPI patches ...\n" if [ -n "$have_quilt" ] ; then ( cd mpi-${mpi_version}/patches ; if [ -e series ] ; then quilt push -a ; else echo "no patches" ; fi ) else ( cd mpi-${mpi_version} ; apply_patches ) fi fi # # Some final blurbs into config.h # [ -n "$debug_support" ] && printf "#define CONFIG_DEBUG_SUPPORT 1\n" >> config.h [ -n "$gen_gc" ] && printf "#define CONFIG_GEN_GC 1\n" >> config.h # # Regenerate config.make # printf "Regenerating config.make ... 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2858 2859

/* Copyright 2009-2014
 * Kaz Kylheku <kaz@kylheku.com>
 * Vancouver, Canada
 * All rights reserved.
 *
 * BSD License:
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in
 *      the documentation and/or other materials provided with the
 *      distribution.
 *   3. The name of the author may not be used to endorse or promote
 *      products derived from this software without specific prior
 *      written permission.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#include <stdio.h>
#include <string.h>
#include <dirent.h>
#include <stdarg.h>
#include <stdlib.h>
#include <setjmp.h>
#include <errno.h>
#include <ctype.h>
#include <wchar.h>
#include <signal.h>
#include "config.h"
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_FCNTL_H
#include <fcntl.h>
#endif
#include <float.h>
#if HAVE_SYS_WAIT
#include <sys/wait.h>
#endif
#if HAVE_SYS_STAT
#include <sys/stat.h>
#endif
#if HAVE_WINDOWS_H
#include <windows.h>
#endif
#if HAVE_MAKEDEV
#include <sys/types.h>
#endif
#include "lib.h"
#include "gc.h"
#include "signal.h"
#include "unwind.h"
#include "stream.h"
#include "utf8.h"
#include "eval.h"

val output_produced;

val stdin_s, stdout_s, stddebug_s, stderr_s, stdnull_s;

val dev_k, ino_k, mode_k, nlink_k, uid_k;
val gid_k, rdev_k, size_k, blksize_k, blocks_k;
val atime_k, mtime_k, ctime_k;
val from_start_k, from_current_k, from_end_k;
val real_time_k, name_k;
val format_s;

static void common_destroy(val obj)
{
  (void) close_stream(obj, nil);
}

static void null_stream_print(val stream, val out)
{
  format(out, lit("#<~s null>"), stream->co.cls, nao);
}

static val null_get_prop(val stream, val ind)
{
  if (ind == name_k)
    return lit("null-stream");
  return nil;
}

static struct strm_ops null_ops = {
  { eq,
    null_stream_print,
    cobj_destroy_stub_op,
    cobj_mark_op,
    cobj_hash_op },
  0, /* put_string */
  0, /*_put_char */
  0, /* put_byte, */
  0, /* get_line, */
  0, /* get_char, */
  0, /* get_byte, */
  0, /* unget_char, */
  0, /* unget_byte, */
  0, /* close, */
  0, /* flush, */
  0, /* seek, */
  null_get_prop,
  0, /* set_prop */
};

val make_null_stream(void)
{
  return cobj((mem_t *) 0, stream_s, &null_ops.cobj_ops);
}

struct stdio_handle {
  FILE *f;
  val descr;
  val unget_c;
  utf8_decoder_t ud;
#if HAVE_FORK_STUFF
  pid_t pid;
#else
  int pid;
#endif
  val mode; /* used by tail */
  unsigned is_rotated; /* used by tail */
  unsigned is_real_time;
};

static void stdio_stream_print(val stream, val out)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
  if (h->pid)
    format(out, lit("#<~s ~s>"), stream->co.cls, h->descr, nao);
  else
    format(out, lit("#<~s ~s ~s>"), stream->co.cls, h->descr, h->pid, nao);
}

static void stdio_stream_destroy(val stream)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
  common_destroy(stream);
  free(h);
}

static void stdio_stream_mark(val stream)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
  gc_mark(h->descr);
  gc_mark(h->mode);
}

static val stdio_maybe_read_error(val stream)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
  if (h->f == 0)
    uw_throwf(file_error_s, lit("error reading ~a: file closed"), stream, nao);
  if (ferror(h->f)) {
    clearerr(h->f);
    uw_throwf(file_error_s, lit("error reading ~a: ~a/~s"),
              stream, num(errno), string_utf8(strerror(errno)), nao);
  }
  return nil;
}

static val stdio_maybe_error(val stream, val action)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
  if (h->f == 0)
    uw_throwf(file_error_s, lit("error ~a ~a: file closed"), stream, action, nao);
  clearerr(h->f);
  uw_throwf(file_error_s, lit("error ~a ~a: ~a/~s"),
            stream, action, num(errno), string_utf8(strerror(errno)), nao);
}

static int se_putc(int ch, FILE *f)
{
  int ret;
  sig_save_enable;
  ret = putc(ch, f);
  sig_restore_enable;
  return ret;
}

static int se_getc(FILE *f)
{
  int ret;
  sig_save_enable;
  ret = getc(f);
  sig_restore_enable;
  return ret;
}

static int se_fflush(FILE *f)
{
  int ret;
  sig_save_enable;
  ret = fflush(f);
  sig_restore_enable;
  return ret;
}

static int stdio_put_char_callback(int ch, mem_t *f)
{
  int ret = se_putc(ch, (FILE *) f) != EOF;
  return ret;
}

static int stdio_get_char_callback(mem_t *f)
{
  return se_getc((FILE *) f);
}

static val stdio_put_string(val stream, val str)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;

  if (stream != std_debug && stream != std_error)
    output_produced = t;

  if (h->f != 0) {
    const wchar_t *s = c_str(str);

    while (*s) {
      if (!utf8_encode(*s++, stdio_put_char_callback, (mem_t *) h->f))
        return stdio_maybe_error(stream, lit("writing"));
    }
    return t;
  }
  return stdio_maybe_error(stream, lit("writing"));
}

static val stdio_put_char(val stream, val ch)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;

  if (stream != std_debug && stream != std_error)
    output_produced = t;

  return h->f != 0 && utf8_encode(c_chr(ch), stdio_put_char_callback, (mem_t *) h->f)
         ? t : stdio_maybe_error(stream, lit("writing"));
}

static val stdio_put_byte(val stream, int b)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;

  if (stream != std_debug && stream != std_error)
    output_produced = t;

  return h->f != 0 && se_putc(b, (FILE *) h->f) != EOF
         ? t : stdio_maybe_error(stream, lit("writing"));
}

static val stdio_flush(val stream)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
  return (h->f != 0 && se_fflush(h->f) == 0)
         ? t : stdio_maybe_error(stream, lit("flushing"));
}

static val stdio_seek(val stream, cnum offset, enum strm_whence whence)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;

  if (h->f != 0) {
    if (offset == 0 && whence == strm_cur) {
      long where = ftell(h->f);
      if (where >= 0)
        return num(where);
    } else {
      if (fseek(h->f, offset, whence) == 0) {
        utf8_decoder_init(&h->ud);
        h->unget_c = nil;
        return t;
      }
    }
  }

  return stdio_maybe_error(stream, lit("seeking"));
}

static val stdio_get_prop(val stream, val ind)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;

  if (ind == real_time_k) {
    return h->is_real_time ? t : nil;
  } else if (ind == name_k) {
    return h->descr;
  }
  return nil;
}

static val stdio_set_prop(val stream, val ind, val prop)
{
  if (ind == real_time_k) {
    struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
    h->is_real_time = prop ? 1 : 0;
    return t;
  }
  return nil;
}

static wchar_t *snarf_line(struct stdio_handle *h)
{
  const size_t min_size = 512;
  size_t size = 0;
  size_t fill = 0;
  wchar_t *buf = 0;

  for (;;) {
    wint_t ch;
   
    if (h->unget_c) {
      ch = c_chr(h->unget_c);
      h->unget_c = nil;
    } else {
      ch = utf8_decode(&h->ud, stdio_get_char_callback, (mem_t *) h->f);
    }

    if (ch == WEOF && buf == 0)
      break;

    if (fill >= size) {
      size_t newsize = size ? size * 2 : min_size;
      buf = (wchar_t *) chk_realloc((mem_t *) buf, newsize * sizeof *buf);
      size = newsize;
    }

    if (ch == '\n' || ch == WEOF) {
      buf[fill++] = 0;
      break;
    }
    buf[fill++] = ch;
  }

  if (buf)
    buf = (wchar_t *) chk_realloc((mem_t *) buf, fill * sizeof *buf);

  return buf;
}

static val stdio_get_line(val stream)
{
  if (stream->co.handle == 0) {
    return stdio_maybe_read_error(stream);
  } else {
    struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
    wchar_t *line = snarf_line(h);
    if (!line)
      return stdio_maybe_read_error(stream);
    return string_own(line);
  }
}

static val stdio_get_char(val stream)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
  val uc = h->unget_c;
  if (uc) {
    h->unget_c = nil;
    return uc;
  }
  if (h->f) {
    wint_t ch = utf8_decode(&h->ud, stdio_get_char_callback, (mem_t *) h->f);
    return (ch != WEOF) ? chr(ch) : stdio_maybe_read_error(stream);
  }
  return stdio_maybe_read_error(stream);
}

static val stdio_get_byte(val stream)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
  if (h->f) {
    int ch = se_getc(h->f);
    return (ch != EOF) ? num(ch) : stdio_maybe_read_error(stream);
  }
  return stdio_maybe_read_error(stream);
}

static val stdio_unget_char(val stream, val ch)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;

  if (!is_chr(ch))
    type_mismatch(lit("unget-char: ~s is not a character"), ch, nao);

  if (h->unget_c)
    uw_throwf(file_error_s, lit("unget-char overflow on ~a: "), stream, nao);

  h->unget_c = ch;
  return ch;
}

static val stdio_unget_byte(val stream, int byte)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;

  return h->f != 0 && ungetc(byte, (FILE *) h->f) != EOF
         ? num_fast(byte)
         : stdio_maybe_error(stream, lit("pushing back byte into"));
}

static val stdio_close(val stream, val throw_on_error)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;

  if (h->f != 0 && h->f != stdin && h->f != stdout) {
    int result = fclose(h->f);
    h->f = 0;
    if (result == EOF && throw_on_error) {
      uw_throwf(file_error_s, lit("error closing ~a: ~a/~s"),
                stream, num(errno), string_utf8(strerror(errno)), nao);
    }
    return result != EOF ? t : nil;
  }
  return nil;
}

static struct strm_ops stdio_ops = {
  { eq,
    stdio_stream_print,
    stdio_stream_destroy,
    stdio_stream_mark,
    cobj_hash_op },
  stdio_put_string,
  stdio_put_char,
  stdio_put_byte,
  stdio_get_line,
  stdio_get_char,
  stdio_get_byte,
  stdio_unget_char,
  stdio_unget_byte,
  stdio_close,
  stdio_flush,
  stdio_seek,
  stdio_get_prop,
  stdio_set_prop
};

static void tail_calc(unsigned long *state, int *sec, int *mod)
{
  unsigned long count = (*state)++;
  if (count > 32)
    count = 32;
  *sec = 1 << (count / 8);
  *mod = 8 >> (count / 8);
  if (*mod == 0)
    *mod = 1;
}

#if !HAVE_POSIX_SLEEP && HAVE_WINDOWS_H

int sleep(int sec);

int sleep(int sec)
{
   Sleep(sec * 1000);
   return 0;
}

#endif

static void tail_strategy(val stream, unsigned long *state)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
  int sec = 0, mod = 0;

  tail_calc(state, &sec, &mod);

  if (h->is_rotated) {
    /* We already know that the file has rotated. The caller
     * has read through to the end of the old open file, and
     * so we can close it now and open a new file.
     */
    fclose(h->f);
    h->f = 0;
    h->is_rotated = 0;
  } else if (h->f != 0) {
    /* We have a file and it hasn't rotated; so sleep on it. */
    sig_save_enable;
    sleep(sec);
    sig_restore_enable;
  }

  /* If the state indicates we should poll for a file rotation,
   * or we have no file ...
   */
  if (h->f == 0 || *state % mod == 0) {
    long save_pos = 0, size;

    if (h->f != 0 && (save_pos = ftell(h->f)) == -1)
      return;

    for (;;) {
      FILE *newf;

      /* Try to open the file. 
       */
      if (!(newf = w_fopen(c_str(h->descr), c_str(h->mode)))) {
        /* If already have the file open previously, and the name
         * does not open any more, then the file has rotated.
         * Have the caller try to read the last bit of data
         * from the old h->f.
         */
        if (h->f) {
          h->is_rotated = 1;
          return;
        }

        /* Unable to open; keep trying. */
        tail_calc(state, &sec, &mod);
        sig_save_enable;
        sleep(sec);
        sig_restore_enable;
        continue;
      }

      /* We opened the new file. If we have no old file,
       * then this is all we have.
       */
      if (!h->f) {
        h->f = newf;
        break;
      }

      /* Obtain size of new file. If we can't, then let's just pretend we never
       * opened it and bail out. 
       */
      if (fseek(newf, 0, SEEK_END) == -1 || (size = ftell(newf)) == -1) {
        fclose(newf);
        return;
      }

      /* The newly opened file is smaller than the previously opened
       * file. The file has rotated and is quite possibly a new object.
       * We just close newf, and let the caller read the last bit of data from
       * the old stream before cutting over.
       */
      if (size < save_pos) {
        /* TODO: optimize: keep newf in the handle so as not to have to
           re-open it again. */
        h->is_rotated = 1;
        fclose(newf);
        return;
      }

      /* Newly opened file is not smaller. We take a gamble and say
       * that it's the same object as h->f, since rotating files 
       * are usually large and it is unlikely that it is a new file
       * which has grown larger than the original. Just in case,
       * though, we take the new file handle. But we do not reset
       * the UTF8 machine.
       */
      if (save_pos)
        fseek(newf, save_pos, SEEK_SET);
      fclose(h->f);
      h->f = newf;
      return;
    }

    utf8_decoder_init(&h->ud);
  }
}

static val tail_get_line(val stream)
{
  unsigned long state = 0;
  val ret;

  while ((ret = stdio_get_line(stream)) == nil)
    tail_strategy(stream, &state);

  return ret;
}

static val tail_get_char(val stream)
{
  unsigned long state = 0;
  val ret;

  while ((ret = stdio_get_char(stream)) == nil)
    tail_strategy(stream, &state);

  return ret;
}

static val tail_get_byte(val stream)
{
  unsigned long state = 0;
  val ret;

  while ((ret = stdio_get_byte(stream)) == nil)
    tail_strategy(stream, &state);

  return ret;
}


static struct strm_ops tail_ops = {
  { eq,
    stdio_stream_print,
    stdio_stream_destroy,
    stdio_stream_mark,
    cobj_hash_op },
  stdio_put_string,
  stdio_put_char,
  stdio_put_byte,
  tail_get_line,
  tail_get_char,
  tail_get_byte,
  stdio_unget_char,
  stdio_unget_byte,
  stdio_close,
  stdio_flush,
  stdio_seek,
  stdio_get_prop,
  stdio_set_prop
};


#if HAVE_FORK_STUFF
static int pipevp_close(FILE *f, pid_t pid)
{
  int status;
  fclose(f);
  sig_save_enable;
  while (waitpid(pid, &status, 0) == -1 && errno == EINTR)
    ;
  sig_restore_enable;
  return status;
}
#endif

static int se_pclose(FILE *f)
{
  int ret;
  sig_save_enable;
  ret = pclose(f);
  sig_restore_enable;
  return ret;
}

static val pipe_close(val stream, val throw_on_error)
{
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;

  if (h->f != 0) {
#if HAVE_FORK_STUFF
    int status = h->pid != 0 ? pipevp_close(h->f, h->pid) : se_pclose(h->f);
#else
    int status = se_pclose(h->f);
#endif
    h->f = 0;

    if (status < 0) {
      if (throw_on_error)
        uw_throwf(process_error_s,
                  lit("unable to obtain status of command ~a: ~a/~s"),
                  stream, num(errno), string_utf8(strerror(errno)), nao);
    } else {
#ifdef HAVE_SYS_WAIT
      if (throw_on_error) {
        if (WIFSIGNALED(status)) {
          int termsig = WTERMSIG(status);
          uw_throwf(process_error_s, lit("pipe ~a terminated by signal ~a"),
                    stream, num(termsig), nao);
#ifndef WIFCONTINUED
#define WIFCONTINUED(X) 0
#endif
        } else if (WIFSTOPPED(status) || WIFCONTINUED(status)) {
          uw_throwf(process_error_s,
                    lit("processes of closed pipe ~a still running"),
                    stream, nao);
        }
      }
      if (WIFEXITED(status)) {
        int exitstatus = WEXITSTATUS(status);
        return num(exitstatus);
      }
#else
      if (status != 0 && throw_on_error)
        uw_throwf(process_error_s, lit("closing pipe ~a failed"), stream, nao);
#endif
      return status == 0 ? zero : nil;
    } 
  }
  return nil;
}

static struct strm_ops pipe_ops = {
  { eq,
    stdio_stream_print,
    stdio_stream_destroy,
    stdio_stream_mark,
    cobj_hash_op },
  stdio_put_string,
  stdio_put_char,
  stdio_put_byte,
  stdio_get_line,
  stdio_get_char,
  stdio_get_byte,
  stdio_unget_char,
  stdio_unget_byte,
  pipe_close,
  stdio_flush,
  0, /* seek: not on pipes */
  stdio_get_prop,
  stdio_set_prop
};

static void string_in_stream_mark(val stream)
{
  val stuff = (val) stream->co.handle;
  gc_mark(stuff);
}

static val find_char(val string, val start, val ch)
{
  const wchar_t *str = c_str(string);
  cnum pos = c_num(start);
  cnum len = c_num(length_str(string));
  wchar_t c = c_chr(ch);

  for (; pos < len; pos++) {
    if (str[pos] == c)
      return num(pos);
  }

  return nil;
}

static val string_in_get_line(val stream)
{
  val pair = (val) stream->co.handle;
  val string = car(pair);
  val pos = cdr(pair);

  if (lt(pos, length_str(string))) {
    val nlpos = find_char(string, pos, chr('\n'));
    val result = sub_str(string, pos, nlpos);
    set(*cdr_l(pair), nlpos ? plus(nlpos, one) : length_str(string));
    return result;
  }

  return nil;
}

static val string_in_get_char(val stream)
{
  val pair = (val) stream->co.handle;
  val string = car(pair);
  val pos = cdr(pair);

  if (lt(pos, length_str(string))) {
    set(*cdr_l(pair), plus(pos, one));
    return chr_str(string, pos);
  }

  return nil;
}

static val string_in_unget_char(val stream, val ch)
{
  val pair = (val) stream->co.handle;
  val string = car(pair);
  val pos = cdr(pair);

  if (pos == zero)
    uw_throwf(file_error_s,
              lit("unget-char: cannot push past beginning of string"), nao);

  pos = minus(pos, one);

  if (chr_str(string, pos) != ch)
    uw_throwf(file_error_s,
              lit("unget-char: ~s doesn't match the character that was read"),
              nao);

  set(*cdr_l(pair), plus(pos, one));
  return ch;
}

static val string_in_get_prop(val stream, val ind)
{
  if (ind == name_k) {
    val pair = (val) stream->co.handle;
    return format(nil, lit("string-stream (~s)"), car(pair), nao);
  }
  return nil;
}

static struct strm_ops string_in_ops = {
  { eq,
    cobj_print_op,
    cobj_destroy_stub_op,
    string_in_stream_mark,
    cobj_hash_op },
  0, /* put_string */
  0, /* put_char */
  0, /* put_byte */
  string_in_get_line,
  string_in_get_char,
  0, /* get_byte */
  string_in_unget_char,
  0, /* unget_byte, */
  0, /* close */
  0, /* flush */
  0, /* TODO: seek */
  string_in_get_prop,
  0  /* set_prop */
};

struct byte_input {
  unsigned char *buf;
  size_t size;
  size_t index;
};

static void byte_in_stream_destroy(val stream)
{
  struct byte_input *bi = (struct byte_input *) stream->co.handle;

  if (bi) {
    free(bi->buf);
    bi->buf = 0;
    free(bi);
    stream->co.handle = 0;
  }
}

static val byte_in_get_byte(val stream)
{
  struct byte_input *bi = (struct byte_input *) stream->co.handle;

  if (bi->index < bi->size)
    return num(bi->buf[bi->index++]);
  return nil;
}

static val byte_in_unget_byte(val stream, int byte)
{
  struct byte_input *bi = (struct byte_input *) stream->co.handle;

  if (bi->index == 0)
    uw_throwf(file_error_s,
              lit("unget-char: cannot push past beginning of byte stream"),
              nao);

  bi->buf[--bi->index] = byte;
  return num_fast(byte);
}

static struct strm_ops byte_in_ops = {
  { eq,
    cobj_print_op,
    byte_in_stream_destroy,
    cobj_mark_op,
    cobj_hash_op },
  0, /* put_string */
  0, /* put_char */
  0, /* put_byte */
  0, /* get_line */
  0, /* get_char */
  byte_in_get_byte,
  0, /* unget_char, */
  byte_in_unget_byte,
  0, /* close */
  0, /* flush */
  0, /* TODO: support seek */
  0, /* get_prop */
  0  /* set_prop */
};


struct string_output {
  wchar_t *buf;
  size_t size;
  size_t fill;
  utf8_decoder_t ud; 
  unsigned char byte_buf[4];
  int head, tail;
};

static void string_out_stream_destroy(val stream)
{
  struct string_output *so = (struct string_output *) stream->co.handle;

  if (so) {
    free(so->buf);
    so->buf = 0;
    free(so);
    stream->co.handle = 0;
  }
}

static int string_out_byte_callback(mem_t *ctx)
{
  struct string_output *so = (struct string_output *) ctx;
  if (so->tail >= so->head)
    return EOF;
  return so->byte_buf[so->tail++];
}

static val string_out_put_char(val stream, val ch);

static val string_out_byte_flush(struct string_output *so, val stream)
{
  val result = nil;

  if (so->tail < so->head) {
    wint_t ch = utf8_decode(&so->ud, string_out_byte_callback, (mem_t *) so);
    int remaining = so->head - so->tail;
    if (remaining != 0)
      memmove(so->byte_buf, so->byte_buf + so->tail, remaining);
    so->head = so->tail = remaining;
    utf8_decoder_init(&so->ud);
    if (ch == WEOF)
      internal_error("unexpected WEOF from utf8_decode");
    result = string_out_put_char(stream, chr(ch));
    so->tail = 0;
  }
  return result;
}

static val string_out_put_string(val stream, val str)
{
  struct string_output *so = (struct string_output *) stream->co.handle;

  if (so == 0)
    return nil;

  while (so->head != so->tail)
    string_out_byte_flush(so, stream);

  {
    const wchar_t *s = c_str(str);
    size_t len = c_num(length_str(str));
    size_t old_size = so->size;
    size_t required_size = len + so->fill + 1;

    if (required_size < len)
      return nil;

    while (so->size <= required_size) {
      so->size *= 2;
      if (so->size < old_size)
        return nil;
    }

    if (so->size != old_size)
      so->buf = (wchar_t *) chk_realloc((mem_t *) so->buf,
                                        so->size * sizeof *so->buf);
    wmemcpy(so->buf + so->fill, s, len + 1);
    so->fill += len;
    return t;
  }
}

static val string_out_put_char(val stream, val ch)
{
  wchar_t onech[] = wini(" ");
  wref(onech)[0] = c_chr(ch);
  return string_out_put_string(stream, auto_str((const wchli_t *) wref(onech)));
}

static val string_out_put_byte(val stream, int ch)
{
  struct string_output *so = (struct string_output *) stream->co.handle;

  if (so == 0)
    return nil;

  so->byte_buf[so->head++] = ch;

  if (so->head >= (int) sizeof so->byte_buf)
    return string_out_byte_flush(so, stream);

  return t;
}

static struct strm_ops string_out_ops = {
  { eq,
    cobj_print_op,
    string_out_stream_destroy,
    cobj_mark_op,
    cobj_hash_op },
  string_out_put_string,
  string_out_put_char,
  string_out_put_byte,
  0, /* get_line */
  0, /* get_char */
  0, /* get_byte */
  0, /* unget_char, */
  0, /* unget_byte, */
  0, /* close */
  0, /* flush */
  0, /* TODO: seek, with fill-with-spaces semantics if past end. */
  0, /* get_prop */
  0  /* set_prop */
};

static void strlist_mark(val stream)
{
  val stuff = (val) stream->co.handle;
  gc_mark(stuff);
}

static val strlist_out_put_string(val stream, val str)
{
  val cell = (val) stream->co.handle;
  cons_bind (lines, strstream, cell);

  for (;;) {
    val length = length_str(str);
    val span_to_newline = compl_span_str(str, lit("\n"));

    if (zerop(length))
      break;

    put_string(sub_str(str, nil, span_to_newline), strstream);

    if (equal(span_to_newline, length))
      break;

    str = sub_str(str, plus(span_to_newline, num(1)), nil);
    push(get_string_from_stream(strstream), &lines);
    strstream = make_string_output_stream();
  }

  set(*car_l(cell), lines);
  set(*cdr_l(cell), strstream);

  return t;
}

static val strlist_out_put_char(val stream, val ch)
{
  val cell = (val) stream->co.handle;
  cons_bind (lines, strstream, cell);

  if (ch == chr('\n')) {
    push(get_string_from_stream(strstream), &lines);
    strstream = make_string_output_stream();
  } else {
    put_char(ch, strstream);
  }

  set(*car_l(cell), lines);
  set(*cdr_l(cell), strstream);

  return t;
}

static struct strm_ops strlist_out_ops = {
  { eq,
    cobj_print_op,
    cobj_destroy_stub_op,
    strlist_mark,
    cobj_hash_op },
  strlist_out_put_string,
  strlist_out_put_char,
  0, /* TODO: put_byte */
  0, /* get_line */
  0, /* get_char */
  0, /* get_byte */
  0, /* unget_char, */
  0, /* unget_byte, */
  0, /* close */
  0, /* flush */
  0, /* seek */
  0, /* get_prop */
  0  /* set_prop */
};

val make_strlist_output_stream(void)
{
  return cobj((mem_t *) cons(nil, make_string_output_stream()), 
              stream_s, &strlist_out_ops.cobj_ops);
}

val get_list_from_stream(val stream)
{
  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s,
               (lit("~a is not a stream"), stream, nao));

  if (stream->co.ops == &strlist_out_ops.cobj_ops) {
    val cell = (val) stream->co.handle;
    cons_bind (lines, strstream, cell);
    val stray = get_string_from_stream(strstream);
    if (!zerop(length_str(stray)))
      push(stray, &lines);
    return nreverse(lines);
  }

  type_mismatch(lit("~s is not a string list stream"), stream);
}

static val dir_get_line(val stream)
{
  DIR *handle = (DIR *) stream->co.handle;

  if (handle == 0) {
    return nil;
  } else {
    for (;;) {
      struct dirent *e = readdir(handle);
      if (!e)
        return nil;
      if (!strcmp(e->d_name, ".") || !strcmp(e->d_name, ".."))
        continue;
      return string_utf8(e->d_name);
    }
  }
}

static val dir_close(val stream, val throw_on_error)
{
  if (stream->co.handle != 0) {
    closedir((DIR *) stream->co.handle);
    stream->co.handle = 0;
    return t;
  }

  return nil;
}

static struct strm_ops dir_ops = {
  { eq,
    cobj_print_op,
    common_destroy,
    cobj_mark_op,
    cobj_hash_op },
  0, /* put_string */
  0, /* put_char */
  0, /* put_byte */
  dir_get_line,
  0, /* get_char */
  0, /* get_byte */
  0, /* unget_char, */
  0, /* unget_byte, */
  dir_close,
  0, /* flush */
  0, /* seek */
  0, /* get_prop */
  0  /* set_prop */
};

static val make_stdio_stream_common(FILE *f, val descr, struct cobj_ops *ops)
{
  struct stdio_handle *h = (struct stdio_handle *) chk_malloc(sizeof *h);
  val stream = cobj((mem_t *) h, stream_s, ops);
  h->f = f;
  h->descr = descr;
  h->unget_c = nil;
  utf8_decoder_init(&h->ud);
  h->pid = 0;
  h->mode = nil;
  h->is_rotated = 0;
#if HAVE_ISATTY
  h->is_real_time = (h->f != 0 && isatty(fileno(h->f)) == 1);
#else
  h->is_real_time = 0;
#endif
  return stream;
}

val make_stdio_stream(FILE *f, val descr)
{
  return make_stdio_stream_common(f, descr, &stdio_ops.cobj_ops);
}

val make_tail_stream(FILE *f, val descr)
{
  val stream = make_stdio_stream_common(f, descr, &tail_ops.cobj_ops);
  stream_set_prop(stream, real_time_k, t);
  return stream;
}

val make_pipe_stream(FILE *f, val descr)
{
  return make_stdio_stream_common(f, descr, &pipe_ops.cobj_ops);
}

#if HAVE_FORK_STUFF
static val make_pipevp_stream(FILE *f, val descr, pid_t pid)
{
  val stream = make_stdio_stream_common(f, descr, &pipe_ops.cobj_ops);
  struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
  h->pid = pid;
  return stream;
}
#endif

val make_string_input_stream(val string)
{
  return cobj((mem_t *) cons(string, zero), stream_s, &string_in_ops.cobj_ops);
}

val make_string_byte_input_stream(val string)
{
  type_assert (stringp(string), (lit("~a is not a string"), string, nao));

  {
    struct byte_input *bi = (struct byte_input *) chk_malloc(sizeof *bi);
    unsigned char *utf8 = utf8_dup_to_uc(c_str(string));
    bi->buf = utf8;
    bi->size = strlen((char *) utf8);
    bi->index = 0;
    return cobj((mem_t *) bi, stream_s, &byte_in_ops.cobj_ops);
  }
}

val make_string_output_stream(void)
{
  struct string_output *so = (struct string_output *) chk_malloc(sizeof *so);
  so->size = 128;
  so->buf = (wchar_t *) chk_malloc(so->size * sizeof so->buf);
  so->fill = 0;
  so->buf[0] = 0;
  utf8_decoder_init(&so->ud);
  so->head = so->tail = 0;
  return cobj((mem_t *) so, stream_s, &string_out_ops.cobj_ops);
}

val get_string_from_stream(val stream)
{
  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s,
               (lit("~a is not a stream"),
                stream, nao));

  if (stream->co.ops == &string_out_ops.cobj_ops) {
    struct string_output *so = (struct string_output *) stream->co.handle;
    val out = nil;

    if (!so)
      return out;

    while (so->head != so->tail)
      out = string_out_byte_flush(so, stream);

    stream->co.handle = 0;

    so->buf = (wchar_t *) chk_realloc((mem_t *) so->buf,
                                      (so->fill + 1) * sizeof *so->buf);
    out = string_own(so->buf);
    free(so);
    return out;
  } else {
    type_assert (stream->co.ops == &string_in_ops.cobj_ops,
                 (lit("~a is not a string stream"), stream, nao));
    {
      val pair = (val) stream->co.handle;
      return pair ? car(pair) : nil;
    }
  }
}

val make_dir_stream(DIR *dir)
{
  return cobj((mem_t *) dir, stream_s, &dir_ops.cobj_ops);
}

val streamp(val obj)
{
  return typeof(obj) == stream_s ? t : nil;
}

val stream_set_prop(val stream, val ind, val prop)
{
  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->set_prop ? ops->set_prop(stream, ind, prop) : nil;
  }
}

val stream_get_prop(val stream, val ind)
{
  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->get_prop ? ops->get_prop(stream, ind) : nil;
  }
}

val real_time_stream_p(val obj)
{
  if (streamp(obj)) {
    struct strm_ops *ops = (struct strm_ops *) obj->co.ops;
    return ops->get_prop ? ops->get_prop(obj, real_time_k) : nil;
  }

  return nil;
}

val close_stream(val stream, val throw_on_error)
{
  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->close ? ops->close(stream, throw_on_error) : nil;
  }
}

val get_line(val stream)
{
  if (!stream)
    stream = std_input;

  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->get_line ? ops->get_line(stream) : nil;
  }
}

val get_char(val stream)
{
  if (!stream)
    stream = std_input;

  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->get_char ? ops->get_char(stream) : nil;
  }
}

val get_byte(val stream)
{
  if (!stream)
    stream = std_input;

  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->get_byte ? ops->get_byte(stream) : nil;
  }
}

val unget_char(val ch, val stream)
{
  stream = default_arg(stream, std_input);

  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->unget_char ? ops->unget_char(stream, ch) : nil;
  }
}

val unget_byte(val byte, val stream)
{
  cnum b = c_num(byte);

  stream = default_arg(stream, std_input);

  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  if (b < 0 || b > 255)
    uw_throwf(file_error_s, lit("unget-byte on ~a: byte value ~a out of range"),
              stream, byte, nao);

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->unget_byte ? ops->unget_byte(stream, b) : nil;
  }
}

struct fmt {
  size_t minsize;
  const char *dec;
  const char *oct;
  const char *hex;
  const char *HEX;
};

static struct fmt fmt_tab[] = {
  { sizeof(short),"%hd",   "%ho",   "%hx",   "%hX"   },
  { sizeof(int),  "%d",    "%o",    "%x",    "%X"    },
  { sizeof(long), "%ld",   "%lo",   "%lx",   "%llX"  },
  { sizeof(cnum), "%lld",  "%llo",  "%llx",  "%llX"  },
  { sizeof(cnum), "%Ld",   "%Lo",   "%Lx",   "%llX"  },
  { sizeof(cnum), "%qd",   "%qo",   "%qx",   "%qX",  },
  { sizeof(cnum), "%I64d", "%I64o", "%I64x", "%I64X" },
  { 0,            0,       0,       0,       0       }
};

static struct fmt *num_fmt;

static void detect_format_string(void)
{
  struct fmt *f;
  char buf[64];
  cnum num = 1234;

  for (f = fmt_tab; f->minsize != 0; f++) {
    memset(buf, 0, sizeof buf);
    if (f->minsize != sizeof num)
      continue;
    if (sprintf(buf, f->dec, num) == 4 && strcmp(buf, "1234") == 0) {
      num_fmt = f;
      break;
    }
  }
}

static val vformat_num(val stream, const char *str,
                       int width, int left, int zeropad, 
                       int precision, int sign)
{
  int sign_char = (str[0] == '-' || str[0] == '+') ? str[0] : 0;
  int digit_len = strlen(str) - (sign_char != 0);
  int padlen = precision > digit_len ? precision - digit_len : 0;
  int total_len = digit_len + padlen + (sign_char || sign); 
  int slack = (total_len < width) ? width - total_len : 0;
  int i;

  if (!left)
    for (i = 0; i < slack; i++)
      if (!put_char(chr(' '), stream))
        return nil;

  if (!zeropad)
    for (i = 0; i < padlen; i++)
      if (!put_char(chr(' '), stream))
        return nil;

  if (sign_char) {
    put_char(chr(sign_char), stream);
    str++;
  } else if (sign) {
    put_char(chr(sign), stream);
  }

  if (zeropad)
    for (i = 0; i < padlen; i++)
      if (!put_char(chr('0'), stream))
        return nil;

  while (*str)
    if (!put_char(chr(*str++), stream))
      return nil;

  if (left)
    for (i = 0; i < slack; i++)
      if (!put_char(chr(' '), stream))
        return nil;

  return t;
}

static val vformat_str(val stream, val str, int width, int left,
                       int precision)
{
  const wchar_t *cstr = c_str(str);
  int len = c_num(length_str(str));
  int truelen = (precision && precision < len) ? precision : len;
  int slack = (truelen < width) ? width - truelen : 0;
  int i;

  if (!left)
    for (i = 0; i < slack; i++)
      if (!put_char(chr(' '), stream))
        return nil;

  for (i = 0; i < truelen; i++)
    if (!put_char(chr(cstr[i]), stream))
      return nil;

  if (left)
    for (i = 0; i < slack; i++)
      if (!put_char(chr(' '), stream))
        return nil;

  return t;
}

val vformat(val stream, val fmtstr, va_list vl)
{
  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    const wchar_t *fmt = c_str(fmtstr);
    enum {
      vf_init, vf_width, vf_digits, vf_star, vf_precision, vf_spec
    } state = vf_init, saved_state = vf_init;
    int width = 0, precision = 0, precision_p = 0, digits = 0;
    int left = 0, sign = 0, zeropad = 0;
    cnum value;
    void *ptr;

    for (;;) {
      val obj;
      wchar_t ch = *fmt++;
      char num_buf[512], *pnum = num_buf;

      switch (state) {
      case vf_init:
        switch (ch) {
        case 0:
          break;
        case '~':
          state = vf_width;
          width = 0;
          left = 0;
          zeropad = 0;
          precision = 0;
          precision_p = 0;
          digits = 0;
          continue;
        default:
          put_char(chr(ch), stream);
          continue;
        }
        break;
      case vf_width:
        switch (ch) {
        case '~':
          put_char(chr('~'), stream);
          state = vf_init;
          continue;
        case '<':
          left = 1;
          continue;
        case ',':
          state = vf_precision;
          continue;
        case '0': case '1': case '2': case '3': case '4': case '5':
        case '6': case '7': case '8': case '9':
          saved_state = state;
          state = vf_digits;
          digits = ch - '0';
          continue;
        case '*':
          saved_state = state;
          state = vf_star;
          continue;
        default:
          state = vf_spec;
          --fmt;
          continue;
        }
        break;
      case vf_precision:
        switch (ch) {
        case '0':
          zeropad = 1;
          continue;
        case '1': case '2': case '3': case '4': case '5':
        case '6': case '7': case '8': case '9':
          saved_state = state;
          state = vf_digits;
          digits = ch - '0';
          continue;
        case '+': case ' ':
          sign = ch;
          continue;
        case '*':
          saved_state = state;
          state = vf_star;
          continue;
        default:
          state = vf_spec;
          --fmt;
          continue;
        }
        break;
      case vf_digits:
        switch (ch) {
        case '0': case '1': case '2': case '3': case '4':
        case '5': case '6': case '7': case '8': case '9':
          digits = (digits * 10) + (ch - '0');
          if (digits > 999999)
            goto toobig;
          continue;
        default:
  do_digits:
          switch (saved_state) {
          case vf_width:
            if (width < 0) {
              width = -digits;
              left = 1;
            } else {
              width = digits;
            }
            if (ch == ',') {
              state = vf_precision;
            } else {
              state = vf_spec;
              --fmt;
            }
            continue;
          case vf_precision:
            precision = digits;
            precision_p = 1;
            state = vf_spec;
            --fmt;
            continue;
          default:
            internal_error("unexpected state in formatter");
          }
        }
        break;
      case vf_star:
        obj = va_arg(vl, val);
        digits = c_num(obj);
        goto do_digits;
        break;
      case vf_spec:
        state = vf_init;
        switch (ch) {
        case 'x': case 'X':
          obj = va_arg(vl, val);
          if (bignump(obj)) {
            int nchars = mp_radix_size(mp(obj), 16); 
            if (nchars >= (int) sizeof (num_buf))
              pnum = (char *) chk_malloc(nchars + 1);
            mp_toradix_case(mp(obj), (unsigned char *) pnum, 16, 1);
          } else {
            const char *fmt = ch == 'x' ? num_fmt->hex : num_fmt->HEX;
            value = c_num(obj);
            if (value < 0) {
              num_buf[0] = '-';
              sprintf(num_buf + 1, fmt, -value);
            } else {
              sprintf(num_buf, fmt, value);
            }
          }
          goto output_num;
        case 'o':
          obj = va_arg(vl, val);
          if (bignump(obj)) {
            int nchars = mp_radix_size(mp(obj), 8); 
            if (nchars >= (int) sizeof (num_buf))
              pnum = (char *) chk_malloc(nchars + 1);
            mp_toradix(mp(obj), (unsigned char *) pnum, 8);
          } else {
            value = c_num(obj);
            sprintf(num_buf, num_fmt->oct, value);
          }
          goto output_num;
        case 'f': case 'e':
          obj = va_arg(vl, val);

          if (obj == nao)
            goto premature;

          {
            double n;

            switch (type(obj)) {
            case BGNUM:
              obj = flo_int(obj);
              /* fallthrough */
            case FLNUM:
              n = c_flo(obj);
              break;
            case NUM:
              n = (double) c_num(obj);
              break;
            default:
              uw_throwf(error_s, lit("format: ~~~a conversion requires "
                                     "numeric arg: ~s given\n"),
                        chr(ch), obj, nao);
            }

            if (!precision_p)
              precision = 3;

            /* guard against num_buf overflow */
            if (precision > 128)
              uw_throwf(error_s, lit("excessive precision in format: ~s\n"),
                        num(precision), nao);

            if (ch == 'e') {
              sprintf(num_buf, "%.*e", precision, n);
              {
                char *dec = strchr(num_buf, '.');
                char *exp = strchr(dec ? dec : num_buf, 'e');

                if (exp) {
                  char *scan = ++exp;

                  if (*scan == '-')
                    *exp++ = *scan++;
                  else if (*scan == '+')
                    scan++;

                  while (*scan == '0')
                    scan++;

                  if (!*scan)
                    *exp++ = '0';
                  else
                    while (*scan)
                      *exp++ = *scan++;

                  *exp = 0;
                }
              }
            } else {
              sprintf(num_buf, "%.*f", precision, n);
            }
            if (!isdigit(num_buf[0]) && !isdigit(num_buf[1])) {
              if (!vformat_str(stream, lit("#<bad-float>"),
                               width, left, 0))
                return nil;
              continue;
            }
            precision = 0;
            goto output_num;
          }
        case 'a': case 's':
          obj = va_arg(vl, val);
          if (obj == nao)
            goto premature;
          switch (type(obj)) {
          case NUM:
            value = c_num(obj);
            sprintf(num_buf, num_fmt->dec, value);
            goto output_num;
          case BGNUM:
            {
              int nchars = mp_radix_size(mp(obj), 10); 
              if (nchars >= (int) sizeof (num_buf))
                pnum = (char *) chk_malloc(nchars + 1);
              mp_toradix(mp(obj), (unsigned char *) pnum, 10);
            }
            goto output_num;
          case FLNUM:
            if (!precision_p)
              precision = DBL_DIG;

            if (precision > 500)
              uw_throwf(error_s, lit("excessive precision in format: ~s\n"),
                        num(precision), nao);

            sprintf(num_buf, "%.*g", precision, obj->fl.n);

            {
              char *dec = strchr(num_buf, '.');
              char *exp = strchr(dec ? dec : num_buf, 'e');

              if (exp) {
                char *scan = ++exp;

                if (*scan == '-')
                  *exp++ = *scan++;
                else if (*scan == '+')
                  scan++;

                while (*scan == '0')
                  scan++;

                while (*scan)
                  *exp++ = *scan++;

                *exp = 0;
              }

              if (ch == 's' && (!precision_p || precision > 0) && !dec && !exp)
                  strcat(num_buf, ".0");
            }

            if (!isdigit(num_buf[0]) && !isdigit(num_buf[1])) {
              if (!vformat_str(stream, lit("#<bad-float>"),
                               width, left, 0))
                return nil;
              continue;
            }

            precision = 0;
            goto output_num;
          default:
            if (width != 0 || precision_p) {
              val str = format(nil, ch == 'a' ? lit("~a") : lit("~s"),
                               obj, nao);
              if (!vformat_str(stream, str, width, left, precision))
                return nil;
              continue;
            }
          }
          if (ch == 'a')
            obj_pprint(obj, stream);
          else
            obj_print(obj, stream);
          continue;
        case 'p':
          ptr = va_arg(vl, void *);
          value = (cnum) ptr;
          sprintf(num_buf, num_fmt->hex, value);
          goto output_num;
        default:
          uw_throwf(error_s, lit("unknown format directive character ~s\n"), 
                    chr(ch), nao);
        output_num:
          {
            val res = vformat_num(stream, pnum, width, left,
                                  zeropad, precision, sign);
            if (pnum != num_buf)
              free(pnum);
            if (!res)
              return nil;
            continue;
          }
        }
        continue;
      }

      break;
    }
  }

  if (va_arg(vl, val) != nao)
    internal_error("unterminated format argument list");
  return t;
premature:
  internal_error("insufficient arguments for format");
toobig:
  internal_error("ridiculous precision or field width in format");
}

val vformat_to_string(val fmtstr, va_list vl)
{
  val stream = make_string_output_stream();
  (void) vformat(stream, fmtstr, vl);
  return get_string_from_stream(stream);
}

val format(val stream, val str, ...)
{
  uses_or2;
  val st = if3(stream == t,
               std_output,
               or2(stream, make_string_output_stream()));
  type_check (st, COBJ);
  type_assert (st->co.cls == stream_s, (lit("~a is not a stream"), st, nao));

  {
    va_list vl;
    val ret;
    va_start (vl, str);
    ret = vformat(st, str, vl);
    va_end (vl);
    return (stream) ? ret : get_string_from_stream(st);
  }
}

val formatv(val stream, val string, val args)
{
  val arg[32], *p = arg;

  for (; args && p - arg < 32; args = cdr(args), p++)
    *p = car(args);

  switch (p - arg) {
  case  0: return format(stream, string,  nao);
  case  1: return format(stream, string, arg[0], nao);
  case  2: return format(stream, string, arg[0], arg[1], nao);
  case  3: return format(stream, string, arg[0], arg[1], arg[2], nao);
  case  4: return format(stream, string, arg[0], arg[1], arg[2], arg[3], nao);
  case  5: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], nao);
  case  6: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], nao);
  case  7: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], nao);
  case  8: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], nao);
  case  9: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], nao);
  case 10: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], nao);
  case 11: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], nao);
  case 12: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], nao);
  case 13: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], nao);
  case 14: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], nao);
  case 15: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], nao);
  case 16: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], nao);
  case 17: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], nao);
  case 18: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], nao);
  case 19: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], nao);
  case 20: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], nao);
  case 21: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], nao);
  case 22: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], arg[21], nao);
  case 23: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], arg[21], arg[22], nao);
  case 24: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], arg[21], arg[22], arg[23], nao);
  case 25: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], arg[21], arg[22], arg[23], arg[24], nao);
  case 26: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], arg[21], arg[22], arg[23], arg[24], arg[25], nao);
  case 27: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], arg[21], arg[22], arg[23], arg[24], arg[25], arg[26], nao);
  case 28: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], arg[21], arg[22], arg[23], arg[24], arg[25], arg[26], arg[27], nao);
  case 29: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], arg[21], arg[22], arg[23], arg[24], arg[25], arg[26], arg[27], arg[28], nao);
  case 30: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], arg[21], arg[22], arg[23], arg[24], arg[25], arg[26], arg[27], arg[28], arg[29], nao);
  case 31: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], arg[21], arg[22], arg[23], arg[24], arg[25], arg[26], arg[27], arg[28], arg[29], arg[30], nao);
  case 32: return format(stream, string, arg[0], arg[1], arg[2], arg[3], arg[4], arg[5], arg[6], arg[7], arg[8], arg[9], arg[10], arg[11], arg[12], arg[13], arg[14], arg[15], arg[16], arg[17], arg[18], arg[19], arg[20], arg[21], arg[22], arg[23], arg[24], arg[25], arg[26], arg[27], arg[28], arg[29], arg[30], arg[31], nao);
  }

  uw_throwf(file_error_s, lit("too many arguments to format"), nao);
  abort();
}

val put_string(val string, val stream)
{
  stream = default_arg(stream, std_output);

  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->put_string ? ops->put_string(stream, string) : nil;
  }
}

val put_char(val ch, val stream)
{
  stream = default_arg(stream, std_output);

  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->put_char ? ops->put_char(stream, ch) : nil;
  }
}

val put_byte(val byte, val stream)
{
  cnum b = c_num(byte);

  stream = default_arg(stream, std_output);

  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  if (b < 0 || b > 255)
    uw_throwf(file_error_s, lit("put-byte on ~a: byte value ~a out of range"),
              stream, byte, nao);

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->put_byte ? ops->put_byte(stream, b) : nil;
  }
}

val put_line(val string, val stream)
{
  return (put_string(default_arg(string, null_string), stream), put_char(chr('\n'), stream));
}

val flush_stream(val stream)
{
  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    return ops->flush ? ops->flush(stream) : t;
  }
}

val seek_stream(val stream, val offset, val whence)
{
  type_check (stream, COBJ);
  type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
                                            stream, nao));

  {
    struct strm_ops *ops = (struct strm_ops *) stream->co.ops;
    enum strm_whence w;
    cnum off = c_num(offset);

    if (whence == from_start_k)
      w = strm_start;
    else if (whence == from_current_k)
      w = strm_cur;
    else if (whence == from_end_k)
      w = strm_end;
    else
      uw_throwf(file_error_s, lit("seek: ~a is not a valid whence argument"),
                whence, nao);
    
    return ops->seek(stream, off, w);
  }
}

#if HAVE_SYS_STAT
static int w_stat(const wchar_t *wpath, struct stat *buf)
{
  char *path = utf8_dup_to(wpath);
  int res = stat(path, buf);
  free(path);
  return res;
}
#endif

val statf(val path)
{
#if HAVE_SYS_STAT
  struct stat st;
  int res = w_stat(c_str(path), &st);

  if (res == -1)
    uw_throwf(file_error_s, lit("unable to stat ~a: ~a/~s"),
              path, num(errno), string_utf8(strerror(errno)), nao);

  return list(dev_k, num(st.st_dev),
              ino_k, num(st.st_ino),
              mode_k, num(st.st_mode),
              nlink_k, num(st.st_nlink),
              uid_k, num(st.st_uid),
              gid_k, num(st.st_gid),
              rdev_k, num(st.st_rdev),
              size_k, num(st.st_size),
#if !HAVE_WINDOWS_H
              blksize_k, num(st.st_blksize),
              blocks_k, num(st.st_blocks),
#else
              blksize_k, zero,
              blocks_k, zero,
#endif
              atime_k, num(st.st_atime),
              mtime_k, num(st.st_mtime),
              ctime_k, num(st.st_ctime),
              nao);
#else
  uw_throwf(file_error_s, lit("stat is not implemented"), nao);
#endif
}

static DIR *w_opendir(const wchar_t *wname)
{
  char *name = utf8_dup_to(wname);
  DIR *d = opendir(name);
  free(name);
  return d;
}


val open_directory(val path)
{
  DIR *d = w_opendir(c_str(path));

  if (!d)
    uw_throwf(file_error_s, lit("error opening directory ~a: ~a/~s"),
              path, num(errno), string_utf8(strerror(errno)), nao);

  return make_dir_stream(d);
}

val open_file(val path, val mode_str)
{
  FILE *f = w_fopen(c_str(path), c_str(default_arg(mode_str, lit("r"))));

  if (!f)
    uw_throwf(file_error_s, lit("error opening ~a: ~a/~s"),
              path, num(errno), string_utf8(strerror(errno)), nao);

  return make_stdio_stream(f, path);
}

val open_tail(val path, val mode_str, val seek_end_p)
{
  val mode = default_arg(mode_str, lit("r"));
  FILE *f = w_fopen(c_str(path), c_str(mode));
  struct stdio_handle *h;
  val stream;
  unsigned long state = 0;

  if (f && default_bool_arg(seek_end_p))
    if (fseek(f, 0, SEEK_END) < 0)
      uw_throwf(file_error_s, lit("error seeking to end of ~a: ~a/~s"),
                path, num(errno), string_utf8(strerror(errno)), nao);

  stream = make_tail_stream(f, path);
  h = (struct stdio_handle *) stream->co.handle;
  h->mode = mode;
  if (!f)
    tail_strategy(stream, &state);
  return stream;
}

val open_command(val path, val mode_str)
{
  FILE *f = w_popen(c_str(path), c_str(default_arg(mode_str, lit("r"))));

  if (!f)
    uw_throwf(file_error_s, lit("error opening pipe ~a: ~a/~s"),
              path, num(errno), string_utf8(strerror(errno)), nao);

  return make_pipe_stream(f, path);
}

#if HAVE_FORK_STUFF
val open_process(val name, val mode_str, val args)
{
  int input = equal(mode_str, lit("r")) || equal(mode_str, lit("rb"));
  int fd[2];
  pid_t pid;
  char **argv = 0, *utf8name = 0;
  val iter;
  int i, nargs;

  args = default_bool_arg(args);
  nargs = c_num(length(args)) + 1;

  if (pipe(fd) == -1) {
    uw_throwf(file_error_s, lit("opening pipe ~a, pipe syscall failed: ~a/~s"),
              name, num(errno), string_utf8(strerror(errno)), nao);
  }

  argv = (char **) chk_malloc((nargs + 2) * sizeof *argv);

  for (i = 0, iter = cons(name, args); iter; i++, iter = cdr(iter)) {
    val arg = car(iter);
    argv[i] = utf8_dup_to(c_str(arg));
  }
  argv[i] = 0;

  utf8name = utf8_dup_to(c_str(name));

  pid = fork();

  if (pid == -1) {
    for (i = 0; i < nargs; i++)
      free(argv[i]);
    free(argv);
    uw_throwf(file_error_s, lit("opening pipe ~a, fork syscall failed: ~a/~s"),
              name, num(errno), string_utf8(strerror(errno)), nao);
  } 
  
  if (pid == 0) {
    if (input) {
      dup2(fd[1], STDOUT_FILENO);
      if (fd[1] != STDOUT_FILENO) /* You never know */
        close(fd[1]);
      close(fd[0]);
    } else {
      dup2(fd[0], STDIN_FILENO);
      if (fd[0] != STDIN_FILENO) /* You never know */
        close(fd[0]);
      close(fd[1]);
    }

    execvp(utf8name, argv);
    _exit(errno);
  } else {
    int whichfd;
    char *utf8mode = utf8_dup_to(c_str(mode_str));
    FILE *f;

    if (input) {
      close(fd[1]);
      whichfd = fd[0];
    } else {
      close(fd[0]);
      whichfd = fd[1];
    }

    for (i = 0; i < nargs; i++)
      free(argv[i]);
    free(argv);

#if HAVE_FCNTL_H
    fcntl(whichfd, F_SETFD, FD_CLOEXEC);
#endif

    if ((f = fdopen(whichfd, utf8mode)) == 0) {
      int status;
      kill(pid, SIGINT);
      kill(pid, SIGTERM);
      while (waitpid(pid, &status, 0) == -1 && errno == EINTR)
        ;
      free(utf8mode);
      uw_throwf(file_error_s, lit("opening pipe ~a, fdopen failed: ~a/~s"),
                name, num(errno), string_utf8(strerror(errno)), nao);
    }

    free(utf8mode);
    /* TODO: catch potential OOM exception here and kill process. */
    return make_pipevp_stream(f, name, pid);
  }
}
#else

static val win_escape_arg(val str)
{
  int bscount = 0, i;
  const wchar_t *s;
  val out = string(L"");

  for (s = c_str(str); *s; s++) {
    switch (*s) {
    case '"':
      for (i = 0; i < bscount; i++)
        string_extend(out, lit("\\\\"));
      string_extend(out, lit("\\\""));
      bscount = 0;
      break;
    case '\\':
      bscount++;
      break;
    default:
      for (i = 0; i < bscount; i++)
        string_extend(out, lit("\\"));
      string_extend(out, chr(*s));
      bscount = 0;
      break;
    }
  }

  for (i = 0; i < bscount; i++)
    string_extend(out, lit("\\"));

  return out;
}

static val win_make_cmdline(val args)
{
  val out = string(L"");

  string_extend(out, pop(&args));
  string_extend(out, lit(" "));

  for (; args; args = cdr(args)) {
    string_extend(out, lit("\""));
    string_extend(out, win_escape_arg(car(args)));
    if (cdr(args))
      string_extend(out, lit("\" "));
    else
      string_extend(out, lit("\""));
  }

  return out;
}

val open_process(val name, val mode_str, val args)
{
  val win_cmdline = win_make_cmdline(cons(name, default_bool_arg(args)));
  return open_command(win_cmdline, mode_str);
}
#endif

static val sh(val command)
{
  char *cmd = utf8_dup_to(c_str(command));
  int status = system(cmd);
  if (status < 0)
    return nil;
#if HAVE_SYS_WAIT
  if (WIFEXITED(status)) {
    int exitstatus = WEXITSTATUS(status);
    return num(exitstatus);
  }
#endif
  return status == 0 ? zero : nil;
}

#if HAVE_FORK_STUFF
static val run(val name, val args)
{
  pid_t pid;
  char **argv = 0, *utf8name = 0;
  val iter;
  int i, nargs;

  args = default_bool_arg(args);
  nargs = c_num(length(args)) + 1;

  argv = (char **) chk_malloc((nargs + 2) * sizeof *argv);

  for (i = 0, iter = cons(name, args); iter; i++, iter = cdr(iter)) {
    val arg = car(iter);
    argv[i] = utf8_dup_to(c_str(arg));
  }
  argv[i] = 0;

  utf8name = utf8_dup_to(c_str(name));

  pid = fork();

  if (pid == -1) {
    for (i = 0; i < nargs; i++)
      free(argv[i]);
    free(argv);
    uw_throwf(file_error_s, lit("opening process ~a, fork syscall failed: ~a/~s"),
              name, num(errno), string_utf8(strerror(errno)), nao);
  } 
  
  if (pid == 0) {
    execvp(utf8name, argv);
    _exit(errno);
  } else {
    int status;
    for (i = 0; i < nargs; i++)
      free(argv[i]);
    free(argv);
    while (waitpid(pid, &status, 0) == -1 && errno == EINTR)
      ;
    if (status < 0)
      return nil;
#if HAVE_SYS_WAIT
    if (WIFEXITED(status)) {
      int exitstatus = WEXITSTATUS(status);
      return num(exitstatus);
    }
#endif
    return status == 0 ? zero : nil;
  }
}
#elif HAVE_WSPAWN
static val run(val command, val args)
{
  const wchar_t **wargv = 0;
  val iter;
  int i, nargs, status;

  args = default_bool_arg(args);
  nargs = c_num(length(args)) + 1;

  wargv = (const wchar_t **) chk_malloc((nargs + 2) * sizeof *wargv);

  for (i = 0, iter = cons(command, args); iter; i++, iter = cdr(iter))
    wargv[i] = c_str(car(iter));
  wargv[i] = 0;

  status = _wspawnvp(_P_WAIT, c_str(command), wargv);
 
  for (i = 0; i < nargs; i++)
    free((void *) wargv[i]);
  free((void *) wargv);

  return (status < 0) ? nil : num(status);
}
#else
static val run(val command, val args)
{
  val win_cmdline = win_make_cmdline(cons(command, default_bool_arg(args)));
  return sh(win_cmdline);
}
#endif

static void cat_stream_print(val stream, val out)
{
  val streams = (val) stream->co.handle;
  format(out, lit("#<~s catenated ~s>"), stream->co.cls, streams, nao);
}

static val cat_get_line(val stream)
{
  val streams = (val) stream->co.handle;

  while (streams) {
    val line = get_line(first(streams));
    if (line)
      return line;
    if ((streams = rest(streams)) != nil)
      stream->co.handle = (mem_t *) streams;
  }

  return nil;
}

static val cat_get_char(val stream)
{
  val streams = (val) stream->co.handle;

  while (streams) {
    val ch = get_char(first(streams));
    if (ch)
      return ch;
    if ((streams = rest(streams)) != nil)
      stream->co.handle = (mem_t *) streams;
  }

  return nil;
}

static val cat_get_byte(val stream)
{
  val streams = (val) stream->co.handle;

  while (streams) {
    val byte = get_byte(first(streams));
    if (byte)
      return byte;
    if ((streams = rest(streams)) != nil)
      stream->co.handle = (mem_t *) streams;
  }

  return nil;
}

static val cat_unget_byte(val stream, int byte)
{
  val streams = (val) stream->co.handle;

  if (!streams) {
    uw_throwf(file_error_s,
              lit("unget-byte on catenated stream ~a: stream list empty"),
              stream, nao);
  } else {
    val stream = car(streams);
    return unget_byte(stream, num_fast(byte));
  }

  return nil;
}

static val cat_unget_char(val stream, val ch)
{
  val streams = (val) stream->co.handle;

  if (!streams) {
    uw_throwf(file_error_s,
              lit("unget-char on catenated stream ~a: stream list empty"),
              stream, nao);
  } else {
    val stream = car(streams);
    return unget_char(stream, ch);
  }
}

static val cat_get_prop(val stream, val ind)
{
  val streams = (val) stream->co.handle;
  if (streams)
    return stream_get_prop(first(streams), ind);
  return nil;
}

static void cat_mark(val stream)
{
  val obj = (val) stream->co.handle;
  gc_mark(obj);
}

static struct strm_ops cat_stream_ops = {
  { eq,
    cat_stream_print,
    cobj_destroy_stub_op,
    cat_mark,
    cobj_hash_op },
  0, /* put_string */
  0, /*_put_char */
  0, /* put_byte, */
  cat_get_line,
  cat_get_char,
  cat_get_byte,
  cat_unget_char,
  cat_unget_byte,
  0, /* close, */
  0, /* flush, */
  0, /* seek, */
  cat_get_prop,
  0, /* set_prop */
};

val make_catenated_stream(val stream_list)
{
  return cobj((mem_t *) stream_list, stream_s, &cat_stream_ops.cobj_ops);
}

val remove_path(val path)
{
  if (w_remove(c_str(path)) < 0)
    uw_throwf(file_error_s, lit("trying to remove ~a: ~a/~s"),
                path, num(errno), string_utf8(strerror(errno)), nao);
  return t;
}

val rename_path(val from, val to)
{
  if (w_rename(c_str(from), c_str(to)) < 0)
    uw_throwf(file_error_s, lit("trying to rename ~a to ~a: ~a/~s"),
                from, to, num(errno), string_utf8(strerror(errno)), nao);
  return t;
}

#if HAVE_MKDIR
val mkdir_wrap(val path, val mode)
{
  char *u8path = utf8_dup_to(c_str(path));
  int err = mkdir(u8path, c_num(default_arg(mode, num_fast(0777))));
  free(u8path);

  if (err < 0)
    uw_throwf(file_error_s, lit("mkdir ~a: ~a/~s"),
              path, num(errno), string_utf8(strerror(errno)), nao);

  return t;
}
#elif HAVE_WINDOWS_H
val mkdir_wrap(val path, val mode)
{
  int err = _wmkdir(c_str(path));

  (void) mode;
  if (err < 0)
    uw_throwf(file_error_s, lit("mkdir ~a: ~a/~s"),
              path, num(errno), string_utf8(strerror(errno)), nao);

  return t;
}
#endif

#if HAVE_UNISTD_H
val chdir_wrap(val path)
{
  char *u8path = utf8_dup_to(c_str(path));
  int err = chdir(u8path);
  free(u8path);

  if (err < 0)
    uw_throwf(file_error_s, lit("chdir ~a: ~a/~s"),
              path, num(errno), string_utf8(strerror(errno)), nao);
  return t;
}

val getcwd_wrap(void)
{
  size_t guess = 256;

  for (;;) {
    char *u8buf = (char *) chk_malloc(guess);

    if (getcwd(u8buf, guess) == 0) {
      free(u8buf);
      if (errno != ERANGE) {
        uw_throwf(file_error_s, lit("getcwd: ~a/~s"),
                  num(errno), string_utf8(strerror(errno)), nao);
      }
      if (2 * guess > guess)
        guess *= 2;
      else
        uw_throwf(file_error_s, lit("getcwd: weird problem"), nao);
    } else {
      val out = string_utf8(u8buf);
      free(u8buf);
      return out;
    }
  }
}

#if HAVE_MAKEDEV

val makedev_wrap(val major, val minor)
{
  return num(makedev(c_num(major), c_num(minor)));
}

val minor_wrap(val dev)
{
  return num(minor(c_num(dev)));
}

val major_wrap(val dev)
{
  return num(major(c_num(dev)));
}

#endif

#if HAVE_MKNOD

val mknod_wrap(val path, val mode, val dev)
{
  char *u8path = utf8_dup_to(c_str(path));
  int err = mknod(u8path, c_num(mode), c_num(default_arg(dev, zero)));
  free(u8path);

  if (err < 0)
#if HAVE_MAKEDEV
    uw_throwf(file_error_s, lit("mknod ~a ~a ~a (~a:~a): ~a/~s"),
              path, mode, dev, major_wrap(dev), minor_wrap(dev), num(errno),
              string_utf8(strerror(errno)), nao);
#else
    uw_throwf(file_error_s, lit("mknod ~a ~a ~a: ~a/~s"),
              path, mode, dev, num(errno),
              string_utf8(strerror(errno)), nao);
#endif

  return t;
}

#endif

#if HAVE_SYMLINK

val symlink_wrap(val target, val to)
{
  char *u8target = utf8_dup_to(c_str(target));
  char *u8to = utf8_dup_to(c_str(to));
  int err = symlink(u8target, u8to);
  free(u8target);
  free(u8to);
  if (err < 0)
    uw_throwf(file_error_s, lit("symlink ~a ~a: ~a/~s"),
              target, to, num(errno), string_utf8(strerror(errno)), nao);
  return t;
}

val link_wrap(val target, val to)
{
  char *u8target = utf8_dup_to(c_str(target));
  char *u8to = utf8_dup_to(c_str(to));
  int err = link(u8target, u8to);
  free(u8target);
  free(u8to);
  if (err < 0)
    uw_throwf(file_error_s, lit("link ~a ~a: ~a/~s"),
              target, to, num(errno), string_utf8(strerror(errno)), nao);
  return t;
}

val readlink_wrap(val path)
{
  char *u8path = utf8_dup_to(c_str(path));
  ssize_t guess = 256;

  for (;;) {
    char *u8buf = (char *) chk_malloc(guess);
    ssize_t bytes = readlink(u8path, u8buf, guess);

    if (bytes >= guess) {
      free(u8buf);
      if (2 * guess > guess)
        guess *= 2;
      else
        uw_throwf(file_error_s, lit("readlink: weird problem"), nao);
    } else if (bytes <= 0) {
      free(u8buf);
      uw_throwf(file_error_s, lit("readlink ~a: ~a/~s"),
                path, num(errno), string_utf8(strerror(errno)), nao);
    } else {
      val out;
      u8buf[bytes] = 0;
      out = string_utf8(u8buf);
      free(u8buf);
      return out;
    }
  }
}

#endif

static val open_files(val file_list, val substitute_stream)
{
  substitute_stream = default_bool_arg(substitute_stream);

  if (nilp(file_list) && substitute_stream) {
    return substitute_stream;
  } else {
    return apply_intrinsic(func_n0v(make_catenated_stream),
                           cons(mapcar(func_n2o(open_file, 1), file_list), nil));

  }
}

static val open_files_star(val file_list, val substitute_stream)
{
  substitute_stream = default_bool_arg(substitute_stream);

  if (nilp(file_list) && substitute_stream) {
    return substitute_stream;
  } else {
    return apply_intrinsic(func_n0v(make_catenated_stream),
                           cons(lazy_mapcar(func_n2o(open_file, 1), file_list), nil));
  }
}

#endif

void stream_init(void)
{
  protect(&std_input, &std_output, &std_debug, &std_error, &std_null, (val *) 0);
  detect_format_string();

  dev_k = intern(lit("dev"), keyword_package);
  ino_k = intern(lit("ino"), keyword_package);
  mode_k = intern(lit("mode"), keyword_package);
  nlink_k = intern(lit("nlink"), keyword_package);
  uid_k = intern(lit("uid"), keyword_package);
  gid_k = intern(lit("gid"), keyword_package);
  rdev_k = intern(lit("rdev"), keyword_package);
  size_k = intern(lit("size"), keyword_package);
  blksize_k = intern(lit("blksize"), keyword_package);
  blocks_k = intern(lit("blocks"), keyword_package);
  atime_k = intern(lit("atime"), keyword_package);
  mtime_k = intern(lit("mtime"), keyword_package);
  ctime_k = intern(lit("ctime"), keyword_package);
  from_start_k = intern(lit("from-start"), keyword_package);
  from_current_k = intern(lit("from-current"), keyword_package);
  from_end_k = intern(lit("from-end"), keyword_package);
  real_time_k = intern(lit("real-time"), keyword_package);
  name_k = intern(lit("name"), keyword_package);
  format_s = intern(lit("format"), user_package);

#ifndef S_IFSOCK
#define S_IFSOCK 0
#endif

#ifndef S_IFLNK
#define S_IFLNK 0
#endif

#ifndef S_ISUID
#define S_ISUID 0
#endif

#ifndef S_ISGID
#define S_ISGID 0
#endif

#ifndef S_ISVTX
#define S_ISVTX 0
#endif

#ifndef S_IRWXG
#define S_IRWXG 0
#endif

#ifndef S_IRGRP
#define S_IRGRP 0
#endif

#ifndef S_IWGRP
#define S_IWGRP 0
#endif

#ifndef S_IXGRP
#define S_IXGRP 0
#endif

#ifndef S_IRWXO
#define S_IRWXO 0
#endif

#ifndef S_IROTH
#define S_IROTH 0
#endif

#ifndef S_IWOTH
#define S_IWOTH 0
#endif

#ifndef S_IXOTH
#define S_IXOTH 0
#endif

#if HAVE_SYS_STAT
  reg_var(intern(lit("s-ifmt"), user_package), num_fast(S_IFMT));
  reg_var(intern(lit("s-ifsock"), user_package), num_fast(S_IFSOCK));
  reg_var(intern(lit("s-iflnk"), user_package), num_fast(S_IFLNK));
  reg_var(intern(lit("s-ifreg"), user_package), num_fast(S_IFREG));
  reg_var(intern(lit("s-ifblk"), user_package), num_fast(S_IFBLK));
  reg_var(intern(lit("s-ifdir"), user_package), num_fast(S_IFDIR));
  reg_var(intern(lit("s-ifchr"), user_package), num_fast(S_IFCHR));
  reg_var(intern(lit("s-ififo"), user_package), num_fast(S_IFIFO));
  reg_var(intern(lit("s-isuid"), user_package), num_fast(S_ISUID));
  reg_var(intern(lit("s-isgid"), user_package), num_fast(S_ISGID));
  reg_var(intern(lit("s-isvtx"), user_package), num_fast(S_ISVTX));
  reg_var(intern(lit("s-irwxu"), user_package), num_fast(S_IRWXU));
  reg_var(intern(lit("s-irusr"), user_package), num_fast(S_IRUSR));
  reg_var(intern(lit("s-iwusr"), user_package), num_fast(S_IWUSR));
  reg_var(intern(lit("s-ixusr"), user_package), num_fast(S_IXUSR));
  reg_var(intern(lit("s-irwxg"), user_package), num_fast(S_IRWXG));
  reg_var(intern(lit("s-irgrp"), user_package), num_fast(S_IRGRP));
  reg_var(intern(lit("s-iwgrp"), user_package), num_fast(S_IWGRP));
  reg_var(intern(lit("s-ixgrp"), user_package), num_fast(S_IXGRP));
  reg_var(intern(lit("s-irwxo"), user_package), num_fast(S_IRWXO));
  reg_var(intern(lit("s-iroth"), user_package), num_fast(S_IROTH));
  reg_var(intern(lit("s-iwoth"), user_package), num_fast(S_IWOTH));
  reg_var(intern(lit("s-ixoth"), user_package), num_fast(S_IXOTH));
#endif

  reg_var(stdin_s = intern(lit("*stdin*"), user_package),
          make_stdio_stream(stdin, lit("stdin")));
  reg_var(stdout_s = intern(lit("*stdout*"), user_package),
          make_stdio_stream(stdout, lit("stdout")));
  reg_var(stddebug_s = intern(lit("*stddebug*"), user_package),
          make_stdio_stream(stdout, lit("debug")));
  reg_var(stderr_s = intern(lit("*stderr*"), user_package),
          make_stdio_stream(stderr, lit("stderr")));
  reg_var(stdnull_s = intern(lit("*stdnull*"), user_package),
          make_null_stream());

  reg_fun(format_s, func_n2v(formatv));
  reg_fun(intern(lit("make-string-input-stream"), user_package), func_n1(make_string_input_stream));
  reg_fun(intern(lit("make-string-byte-input-stream"), user_package), func_n1(make_string_byte_input_stream));
  reg_fun(intern(lit("make-string-output-stream"), user_package), func_n0(make_string_output_stream));
  reg_fun(intern(lit("get-string-from-stream"), user_package), func_n1(get_string_from_stream));
  reg_fun(intern(lit("make-strlist-output-stream"), user_package), func_n0(make_strlist_output_stream));
  reg_fun(intern(lit("get-list-from-stream"), user_package), func_n1(get_list_from_stream));
  reg_fun(intern(lit("close-stream"), user_package), func_n2o(close_stream, 1));
  reg_fun(intern(lit("get-line"), user_package), func_n1o(get_line, 0));
  reg_fun(intern(lit("get-char"), user_package), func_n1o(get_char, 0));
  reg_fun(intern(lit("get-byte"), user_package), func_n1o(get_byte, 0));
  reg_fun(intern(lit("put-string"), user_package), func_n2o(put_string, 1));
  reg_fun(intern(lit("put-line"), user_package), func_n2o(put_line, 0));
  reg_fun(intern(lit("put-char"), user_package), func_n2o(put_char, 1));
  reg_fun(intern(lit("put-byte"), user_package), func_n2o(put_byte, 1));
  reg_fun(intern(lit("unget-char"), user_package), func_n2o(unget_char, 1));
  reg_fun(intern(lit("unget-byte"), user_package), func_n2o(unget_byte, 1));
  reg_fun(intern(lit("flush-stream"), user_package), func_n1(flush_stream));
  reg_fun(intern(lit("seek-stream"), user_package), func_n3(seek_stream));
  reg_fun(intern(lit("stat"), user_package), func_n1(statf));
  reg_fun(intern(lit("streamp"), user_package), func_n1(streamp));
  reg_fun(intern(lit("real-time-stream-p"), user_package), func_n1(real_time_stream_p));
  reg_fun(intern(lit("stream-set-prop"), user_package), func_n3(stream_set_prop));
  reg_fun(intern(lit("stream-get-prop"), user_package), func_n2(stream_get_prop));
  reg_fun(intern(lit("make-catenated-stream"), user_package), func_n0v(make_catenated_stream));

  reg_fun(intern(lit("open-directory"), user_package), func_n1(open_directory));
  reg_fun(intern(lit("open-file"), user_package), func_n2o(open_file, 1));
  reg_fun(intern(lit("open-tail"), user_package), func_n3o(open_tail, 1));
  reg_fun(intern(lit("open-command"), user_package), func_n2o(open_command, 1));
  reg_fun(intern(lit("open-pipe"), user_package), func_n2(open_command));
  reg_fun(intern(lit("open-process"), user_package), func_n3o(open_process, 2));
  reg_fun(intern(lit("sh"), user_package), func_n1(sh));
  reg_fun(intern(lit("run"), user_package), func_n2o(run, 1));
  reg_fun(intern(lit("remove-path"), user_package), func_n1(remove_path));
  reg_fun(intern(lit("rename-path"), user_package), func_n2(rename_path));
  reg_fun(intern(lit("open-files"), user_package), func_n2o(open_files, 1));
  reg_fun(intern(lit("open-files*"), user_package), func_n2o(open_files_star, 1));
}