/* * Copyright (c) 2006 Darren Tucker * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include "includes.h" #include #include #include #include #include #include #define NUM_OPENS 10 void fail(char *msg) { fprintf(stderr, "closefrom: %s\n", msg); exit(1); } int main(void) { int i, max, fds[NUM_OPENS]; char buf[512]; for (i = 0; i < NUM_OPENS; i++) if ((fds[i] = open("/dev/null", O_RDONLY)) == -1) exit(0); /* can't test */ max = i - 1; /* should close last fd only */ closefrom(fds[max]); if (close(fds[max]) != -1) fail("failed to close highest fd"); /* make sure we can still use remaining descriptors */ for (i = 0; i < max; i++) if (read(fds[i], buf, sizeof(buf)) == -1) fail("closed descriptors it should not have"); /* should close all fds */ closefrom(fds[0]); for (i = 0; i < NUM_OPENS; i++) if (close(fds[i]) != -1) fail("failed to close from lowest fd"); return 0; }