fstat: take fd argument.

* sysif.c (get_fd): Make available under HAVE_SYS_STAT.
(fstat): Allow fd or stream argument using get_fd.

* txr.1: Documented.

2 files changed, 14 insertions, 15 deletions

diff --git a/sysif.c b/sysif.c
index 8e9457d0..90f38ee9 100644
--- a/sysif.c
+++ b/sysif.c
@@ -449,8 +449,7 @@ static val mknod_wrap(val path, val mode, val dev)
 
 #endif
 
-#if HAVE_CHMOD
-
+#if HAVE_CHMOD || HAVE_SYS_STAT
 static int get_fd(val stream, val self)
 {
   val fd_in = if3(integerp(stream), stream, stream_get_prop(stream, fd_k));
@@ -467,6 +466,9 @@ static int get_fd(val stream, val self)
 
   return c_int(fd_in, self);
 }
+#endif
+
+#if HAVE_CHMOD
 
 static val chmod_wrap(val target, val mode)
 {
@@ -790,16 +792,9 @@ static int w_lstat(val wpath, struct stat *buf)
 
 static int w_fstat(val stream, struct stat *buf)
 {
-  val fd = stream_get_prop(stream, fd_k);
-
-  if (fd) {
-    int res = fstat(c_num(fd), buf);
-    return res;
-  }
-
-  uw_throwf(file_error_s,
-            lit("cannot fstat stream ~s: it has no :fd property"),
-            stream, nao);
+  val self = lit("fstat");
+  int fd = get_fd(stream, self);
+  return fstat(fd, buf);
 }
 #endif
 
diff --git a/txr.1 b/txr.1
index 0624f488..82533914 100644
--- a/txr.1
+++ b/txr.1
@@ -57697,7 +57697,7 @@ fields take on values of zero.
 .synb
 .mets (stat << path )
 .mets (lstat << path )
-.mets (fstat << stream )
+.mets (fstat > { stream | << fd })
 .syne
 .desc
 The
@@ -57731,8 +57731,12 @@ The
 .code fstat
 function retrieves information about the file system object associated with
 the open stream
-.metn stream .
-The stream must be of a kind from which the
+.meta stream
+or numeric file descriptor
+.metn fd .
+If a
+.meta stream
+is specified, that stream must be of a kind from which the
 .code fileno
 function can retrieve a file descriptor, otherwise an exception of type
 .code file-error