in perl, how do we detect a segmentation fault in an external command

Question

Following is C code that is destined to crash:

#include
#include

int main() {
    char *p = NULL;
    printf(\"Value at P: %c         


        

Answer 1

Reading the documentation for system might answer your question:

system('a.out');

if ($? == -1) {
    print "failed to execute: $!\n";
}
elsif ($? & 127) {
    printf "child died with signal %d, %s coredump\n",
        ($? & 127),  ($? & 128) ? 'with' : 'without';
}
else {
    printf "child exited with value %d\n", $? >> 8;
}

Output:

child died with signal 11, without coredump

The shell just encodes the signal in the status in a different way: 139 - 128 = 11. For example, man bash says:

The return value of a simple command is its exit status, or 128+n if the command is terminated by signal n.