39 lines
719 B
C
39 lines
719 B
C
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#include <unistd.h>
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#include <signal.h>
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static void sig_alrm(int signo) {
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}
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unsigned int sleep(unsigned int seconds) {
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struct sigaction newact, oldact;
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sigset_t newmask, oldmask, suspmask;
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unsigned int unslept;
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newact.sa_handler = sig_alrm;
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sigemptyset(&newact.sa_mask);
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newact.sa_flags = 0;
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sigaction(SIGALRM, &newact, &oldact);
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sigemptyset(&newmask);
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sigaddset(&newmask, SIGALRM);
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sigprocmask(SIG_BLOCK, &newmask, &oldmask);
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alarm(seconds);
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suspmask = oldmask;
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sigdelset(&suspmask, SIGALRM);
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sigsuspend(&suspmask);
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unslept = alarm(0);
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sigaction(SIGALRM, &oldact, NULL);
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sigprocmask(SIG_SETMASK, &oldmask, NULL);
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return unslept;
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}
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int main(void) {
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return sleep(5);
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}
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