51 lines
936 B
C
51 lines
936 B
C
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#include <signal.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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static void sig_quit(int);
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int main(void) {
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sigset_t newmask, oldmask, pendmask;
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if (signal(SIGQUIT, sig_quit) == SIG_ERR) {
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printf("can't catch SIGQUIT\n");
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return -1;
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}
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sigemptyset(&newmask);
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sigaddset(&newmask, SIGQUIT);
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if (sigprocmask(SIG_BLOCK, &newmask, &oldmask) < 0) {
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printf("SIG_BLOCK error\n");
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return -1;
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}
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sleep(5);
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if (sigpending(&pendmask) < 0) {
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printf("sigpeding error\n");
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return -1;
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}
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if (sigismember(&pendmask, SIGQUIT)) {
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printf("\nSIGQUIT pending\n");
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}
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if (sigprocmask(SIG_SETMASK, &oldmask, NULL) < 0) {
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printf("SIG_SETMASK error\n");
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return -1;
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}
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printf("SIGQUIT unblocked\n");
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sleep(5);
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return 0;
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}
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static void sig_quit(int signo) {
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printf("caught SIGQUIT\n");
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if (signal(SIGQUIT, SIG_DFL) == SIG_ERR) {
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printf("can't reset SIGQUIT");
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}
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}
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