59 lines
870 B
C
59 lines
870 B
C
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/* To determine the semantics of signal handlers
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(System V: signal is reset to default behavior on entrance to the handler
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BSD: signal handler remains active). */
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#include <stdio.h>
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#include <signal.h>
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/* Find a signal that is ignored by default */
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#ifdef SIGCHLD
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#define IGNSIG SIGCHLD
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#else
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#ifdef SIGIO
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#define IGNSIG SIGIO
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#else
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#ifdef SIGCLD
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#define IGNSIG SIGCLD
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#else
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#ifdef SIGPWR
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#define IGNSIG SIGPWR
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#endif
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#endif
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#endif
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#endif
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#ifdef IGNSIG
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int counter;
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void sig_handler(dummy)
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int dummy;
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{
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counter++;
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}
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int main(argc, argv)
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int argc;
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char ** argv;
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{
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signal(IGNSIG, sig_handler);
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counter = 0;
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kill(getpid(), IGNSIG);
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kill(getpid(), IGNSIG);
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return (counter == 2 ? 0 : 1);
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}
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#else
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/* If no suitable signal was found, assume System V */
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int main(argc, argv)
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int argc;
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char ** argv;
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{
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return 1;
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}
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#endif
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