/* * Copyright (c) International Business Machines Corp., 2001 * * 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 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 * 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 * * NAME * fork08.c * * DESCRIPTION * Check if the parent's file descriptors are affected by * actions in the child; they should not be. * * ALGORITHM * Parent opens a file. * Forks a child which closes a file. * Parent forks a second child which attempts to read the (closed) * file. * * USAGE * fork08 * * HISTORY * 07/2001 Ported by Wayne Boyer * * RESTRICTIONS * None */ #include #include #include #include #include "test.h" char *TCID = "fork08"; int TST_TOTAL = 1; static void setup(void); static void cleanup(void); static char pbuf[10]; static char fnamebuf[40]; int main(int ac, char **av) { int status, count, forks, pid1; int ch_r_stat; FILE *rea, *writ; int lc; tst_parse_opts(ac, av, NULL, NULL); setup(); for (lc = 0; TEST_LOOPING(lc); lc++) { tst_count = 0; writ = fopen(fnamebuf, "w"); if (writ == NULL) tst_resm(TFAIL, "failed to fopen file for write"); rea = fopen(fnamebuf, "r"); if (rea == NULL) tst_resm(TFAIL, "failed to fopen file for read"); fprintf(writ, "abcdefghijklmnopqrstuv"); fflush(writ); sleep(1); if ((getc(rea)) != 'a') tst_resm(TFAIL, "getc from read side was confused"); forks = 0; forkone: ++forks; pid1 = fork(); if (pid1 != 0) { tst_resm(TINFO, "parent forksval: %d", forks); if ((pid1 != (-1)) && (forks < 2)) goto forkone; else if (pid1 < 0) tst_resm(TINFO, "Fork failed"); } else { /* child */ /* * If first child close the file descriptor for the * read stream */ if (forks == 1) { if ((fclose(rea)) == -1) { tst_resm(TFAIL, "error in first child" " closing fildes"); } _exit(0); } /* * If second child attempt to read from the file */ else if (forks == 2) { ch_r_stat = getc(rea); tst_resm(TINFO, "second child got char: %c", ch_r_stat); if (ch_r_stat == 'b') { tst_resm(TPASS, "Test passed in child" "number %d", forks); exit(0); } else if (ch_r_stat == EOF) { tst_resm(TFAIL, "Second child got " "EOF"); exit(-1); } else { tst_resm(TFAIL, "test failed in child" "no %d", forks); exit(-1); } } else { /* end of second child */ tst_resm(TINFO, "forksnumber: %d", forks); exit(3); } } for (count = 0; count <= forks; count++) { wait(&status); tst_resm(TINFO, "exit status of wait " " expected 0 got %d", status); status >>= 8; if (status == 0) tst_resm(TPASS, "parent test PASSED"); else tst_resm(TFAIL, "parent test FAILED"); } tst_resm(TINFO, "Number of processes forked is %d", forks); fclose(rea); fclose(writ); } cleanup(); tst_exit(); } static void setup(void) { tst_sig(FORK, DEF_HANDLER, cleanup); umask(0); TEST_PAUSE; tst_tmpdir(); strcpy(fnamebuf, "fork07."); sprintf(pbuf, "%d", getpid()); strcat(fnamebuf, pbuf); } static void cleanup(void) { tst_rmdir(); }