1 
2 #include <signal.h>
3 #include <stdio.h>
4 #include <stdlib.h>
5 #include <unistd.h>
6 
7 static struct sigaction oldChildHandlerData;
8 
theHandler(int arg)9 void theHandler(int arg)
10 {
11   printf("handled %s\n", arg == SIGCHLD ? "SIGCHLD" : "?!unexpected signal?!" );
12 }
13 
setupHandlers()14 void setupHandlers()
15 {
16   struct sigaction act;
17   act.sa_handler=theHandler;
18   sigemptyset(&(act.sa_mask));
19   sigaddset(&(act.sa_mask), SIGCHLD);
20   // Make sure we don't block this signal. gdb tends to do that :-(
21   sigprocmask(SIG_UNBLOCK, &(act.sa_mask), 0);
22 
23   act.sa_flags = SA_NOCLDSTOP;
24 
25   // CC: take care of SunOS which automatically restarts interrupted system
26   // calls (and thus does not have SA_RESTART)
27 
28 #ifdef SA_RESTART
29   act.sa_flags |= SA_RESTART;
30 #endif
31 
32   sigaction( SIGCHLD, &act, &oldChildHandlerData );
33 
34   act.sa_handler=SIG_IGN;
35   sigemptyset(&(act.sa_mask));
36   sigaddset(&(act.sa_mask), SIGPIPE);
37   act.sa_flags = 0;
38   sigaction( SIGPIPE, &act, 0L);
39 }
40 
main()41 int main()
42 {
43     char buffer[200];
44     setupHandlers();
45     FILE *p = popen("echo Hallo World", "r");
46     while (!feof(p)) {
47         int n = fread(buffer, 200, 1, p);
48         __attribute__((unused)) ssize_t nw = write(2, buffer, n);
49     }
50     pclose(p);
51     return 0;
52 }
53