/* closeout.c - close standard output Copyright (C) 1998, 1999 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #if HAVE_CONFIG_H # include #endif #if ENABLE_NLS # include # define _(Text) gettext (Text) #else # define _(Text) Text #endif #if HAVE_STDLIB_H # include #endif #ifndef EXIT_FAILURE # define EXIT_FAILURE 1 #endif #include #ifndef errno extern int errno; #endif #include #include "closeout.h" #include "error.h" /* Close standard output, exiting with status STATUS on failure. If a program writes *anything* to stdout, that program should `fflush' stdout and make sure that it succeeds before exiting. Otherwise, suppose that you go to the extreme of checking the return status of every function that does an explicit write to stdout. The last printf can succeed in writing to the internal stream buffer, and yet the fclose(stdout) could still fail (due e.g., to a disk full error) when it tries to write out that buffered data. Thus, you would be left with an incomplete output file and the offending program would exit successfully. FIXME: note the fflush suggested above is implicit in the fclose we actually do below. Consider doing only the fflush and/or using setvbuf to inhibit buffering. Besides, it's wasteful to check the return value from every call that writes to stdout -- just let the internal stream state record the failure. That's what the ferror test is checking below. 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_status (int status) { if (ferror (stdout)) error (status, 0, _("write error")); if (fclose (stdout) != 0) error (status, errno, _("write error")); } /* Close standard output, exiting with status EXIT_FAILURE on failure. */ void close_stdout (void) { close_stdout_status (EXIT_FAILURE); }