X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fsafe-write.h;h=30f6e799f33f8f40429151d16a78715d29125fb9;hb=05c9fb114d40810816df58c1e948ba3c93a4a147;hp=25d1a4d487617b5bed41364dc667b116e13732d3;hpb=849efe7683e163ede9240b27d675977c71c76ce8;p=gnulib.git

diff --git a/lib/safe-write.h b/lib/safe-write.h
index 25d1a4d48..30f6e799f 100644
--- a/lib/safe-write.h
+++ b/lib/safe-write.h
@@ -1,10 +1,10 @@
 /* An interface to write() that retries after interrupts.
-   Copyright (C) 2002 Free Software Foundation, Inc.
+   Copyright (C) 2002, 2009-2013 Free Software Foundation, Inc.
 
-   This program is free software; you can redistribute it and/or modify
+   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.
+   the Free Software Foundation; either version 3 of the License, 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
@@ -12,12 +12,26 @@
    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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Some system calls may be interrupted and fail with errno = EINTR in the
+   following situations:
+     - The process is stopped and restarted (signal SIGSTOP and SIGCONT, user
+       types Ctrl-Z) on some platforms: Mac OS X.
+     - The process receives a signal for which a signal handler was installed
+       with sigaction() with an sa_flags field that does not contain
+       SA_RESTART.
+     - The process receives a signal for which a signal handler was installed
+       with signal() and for which no call to siginterrupt(sig,0) was done,
+       on some platforms: AIX, HP-UX, IRIX, OSF/1, Solaris.
+
+   This module provides a wrapper around write() that handles EINTR.  */
 
 #include <stddef.h>
 
+#define SAFE_WRITE_ERROR ((size_t) -1)
+
 /* Write up to COUNT bytes at BUF to descriptor FD, retrying if interrupted.
-   Return the actual number of bytes written, zero for EOF, or (size_t) -1
-   for an error.  */
+   Return the actual number of bytes written, zero for EOF, or SAFE_WRITE_ERROR
+   upon error.  */
 extern size_t safe_write (int fd, const void *buf, size_t count);