1
2#include <signal.h>
3#include <stdio.h>
4#include <stdlib.h>
5#include <unistd.h>
6
7static struct sigaction oldChildHandlerData;
8
9void theHandler(int arg)
10{
11  printf("handled %s\n", arg == SIGCHLD ? "SIGCHLD" : "?!unexpected signal?!" );
12}
13
14void 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
41int 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