/* Test of SIGPIPE handling. Copyright (C) 2008-2013 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 3, 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, see . */ #include #include /* Check that SIGPIPE is defined. */ int s = SIGPIPE; #include #include #include #include static void handler (int sig) { exit (0); } int main (int argc, char **argv) { char mode = argv[1][0]; switch (mode) { case 'A': signal (SIGPIPE, SIG_DFL); break; case 'B': signal (SIGPIPE, SIG_IGN); break; case 'C': signal (SIGPIPE, handler); break; } /* Produce infinite output. Since it is piped into "head -1", the writes must ultimately fail. */ for (;;) { char c[2] = { 'y', '\n' }; int ret = write (1, c, sizeof (c)); if (ret <= 0) { switch (mode) { case 'B': /* The write() call should have failed with EPIPE. */ if (ret < 0 && errno == EPIPE) exit (0); /*FALLTHROUGH*/ case 'A': /* The process should silently die. */ case 'C': /* The handler should have been called. */ fprintf (stderr, "write() returned %d with error %d.\n", ret, errno); exit (1); } } } }