/* Close standard output and standard error, exiting with a diagnostic on error. Copyright (C) 1998, 1999, 2000, 2001, 2002, 2004, 2006 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include <config.h> #include "closeout.h" #include <errno.h> #include <stdio.h> #include <unistd.h> #include "gettext.h" #define _(msgid) gettext (msgid) #include "close-stream.h" #include "error.h" #include "exitfail.h" #include "quotearg.h" static const char *file_name; /* Set the file name to be reported in the event an error is detected by close_stdout. */ void close_stdout_set_file_name (const char *file) { file_name = file; } /* Close standard output. On error, issue a diagnostic and _exit with status 'exit_failure'. Also close standard error. On error, _exit with status 'exit_failure'. Since close_stdout is commonly registered via 'atexit', POSIX and the C standard both say that it should not call 'exit', because the behavior is undefined if 'exit' is called more than once. So it calls '_exit' instead of 'exit'. If close_stdout is registered via atexit before other functions are registered, the other functions can act before this _exit is invoked. Applications that use close_stdout should flush any streams other than stdout and stderr before exiting, since the call to _exit will bypass other buffer flushing. Applications should be flushing and closing other streams anyway, to check for I/O errors. Also, applications should not use tmpfile, since _exit can bypass the removal of these files. It's important to detect such failures and exit nonzero because many tools (most notably `make' and other build-management systems) depend on being able to detect failure in other tools via their exit status. */ void close_stdout (void) { if (close_stream (stdout) != 0) { char const *write_error = _("write error"); if (file_name) error (0, errno, "%s: %s", quotearg_colon (file_name), write_error); else error (0, errno, "%s", write_error); _exit (exit_failure); } if (close_stream (stderr) != 0) _exit (exit_failure); }