diff lib/safe-read.c @ 148:8124cd69ac96

GNU file utilities
author Jim Meyering <jim@meyering.net>
date Wed, 26 Jan 1994 18:40:49 +0000
parents
children b701d2d6b404
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--- /dev/null
+++ b/lib/safe-read.c
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+/* safe-read.c -- an interface to read that retries after interrupts
+   Copyright (C) 1993, 1994 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+#ifdef HAVE_CONFIG_H
+#if defined (CONFIG_BROKETS)
+/* We use <config.h> instead of "config.h" so that a compilation
+   using -I. -I$srcdir will use ./config.h rather than $srcdir/config.h
+   (which it would do because it found this file in $srcdir).  */
+#include <config.h>
+#else
+#include "config.h"
+#endif
+#endif
+
+#include <sys/types.h>
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#include <errno.h>
+#ifndef STDC_HEADERS
+extern int errno;
+#endif
+
+/* Read LEN bytes at PTR from descriptor DESC, retrying if interrupted.
+   Return the actual number of bytes read, zero for EOF, or negative
+   for an error.  */
+
+int
+safe_read (desc, ptr, len)
+     int desc;
+     char *ptr;
+     int len;
+{
+  int n_chars;
+
+  if (len <= 0)
+    return len;
+
+#ifdef EINTR
+  do
+    {
+      n_chars = read (desc, ptr, len);
+    }
+  while (n_chars < 0 && errno == EINTR);
+#else
+  n_chars = read (desc, ptr, len);
+#endif
+
+  return n_chars;
+}