2002-04-29 Jeff Johnston <jjohnstn@redhat.com>

        *  libc/include/sys/unistd.h (pread, pwrite): Added prototypes.
        *  libc/unix/Makefile.am: Add pread.c and pwrite.c.
        *  libc/sys/linux/Makefile.am: Add pread64.c and pwrite64.c.
        *  libc/sys/linux/Makefile.in: Regenerated.
        *  libc/unix/Makefile.in: Ditto.
        *  libc/sys/linux/pread64.c: New file.
        *  libc/sys/linux/pwrite64.c: Ditto.
        *  libc/unix/pread.c: Ditto.
        *  libc/unix/pwrite.c: Ditto.

1 files changed, 91 insertions, 0 deletions

diff --git a/newlib/libc/unix/pread.c b/newlib/libc/unix/pread.c
new file mode 100644
index 000000000..68ed68eb1
--- /dev/null
+++ b/newlib/libc/unix/pread.c
@@ -0,0 +1,91 @@
+/*
+FUNCTION
+<<pread>>---read a file from specified position
+
+INDEX
+	pread
+INDEX
+	_pread_r
+
+ANSI_SYNOPSIS
+	#include <unistd.h>
+	ssize_t pread(int <[fd]>, void *<[buf]>, size_t <[n]>, off_t <[off]>);
+	ssize_t _pread_r(struct _reent *<[rptr]>, int <[fd]>, 
+                         void *<[buf]>, size_t <[n]>, off_t <[off]>);
+
+TRAD_SYNOPSIS
+	#include <unistd.h>
+	ssize_t pread(<[fd]>, <[buf]>, <[n]>, <[off]>)
+	int <[fd]>;
+	void *<[buf]>;
+	size_t <[n]>;
+	off_t <[off]>;
+
+	ssize_t _pread_r(<[rptr]>, <[fd]>, <[buf]>, <[n]>, <[off]>)
+	struct _reent *<[rptr]>;
+	int <[fd]>;
+	void *<[buf]>;
+	size_t <[n]>;
+	off_t <[off]>;
+
+DESCRIPTION
+The <<pread>> function is similar to <<read>>.  One difference is that
+<<pread>> has an additional parameter <[off]> which is the offset to
+position in the file before reading.  The function also differs in that
+the file position is unchanged by the function (i.e. the file position
+is the same before and after a call to <<pread>>).
+
+The <<_pread_r>> function is the same as <<pread>>, only a reentrant
+struct pointer <[rptr]> is provided to preserve reentrancy.
+
+RETURNS
+<<pread>> returns the number of bytes read or <<-1>> if failure occurred.
+
+PORTABILITY
+<<pread>> is non-ANSI and is specified by the Single Unix Specification.
+
+Supporting OS subroutine required: <<read>>, <<lseek>>.
+*/
+
+#include <_ansi.h>
+#include <unistd.h>
+#include <reent.h>
+
+ssize_t
+_DEFUN (pread_r, (rptr, fd, buf, n, off),
+     struct _reent *rptr _AND
+     int fd _AND
+     _PTR buf _AND
+     size_t n _AND
+     off_t off)
+{
+  off_t cur_pos;
+  _READ_WRITE_RETURN_TYPE num_read;
+  
+  if ((cur_pos = _lseek_r (rptr, fd, 0, SEEK_CUR)) == (off_t)-1)
+    return -1;
+
+  if (_lseek_r (rptr, fd, off, SEEK_SET) == (off_t)-1)
+    return -1;
+
+  num_read = _read_r (rptr, fd, buf, n);
+
+  if (_lseek_r (rptr, fd, cur_pos, SEEK_SET) == (off_t)-1)
+    return -1;
+
+  return (ssize_t)num_read;
+}
+
+#ifndef _REENT_ONLY
+
+ssize_t
+_DEFUN (pread, (fd, buf, n, off),
+     int fd _AND
+     _PTR buf _AND
+     size_t n _AND
+     off_t off)
+{
+  return _pread_r (_REENT, fd, buf, n, off);
+}
+
+#endif