I am debugging an issue with a compiled program written in c++ that is being called from a perl script. If I create a shell script that calls the compiled program directly:

#!/bin/tcsh

myexecutable

exit
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And then run it, the last 2 lines written to the console are:

right before out-of-bounds array access
Segmentation fault
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If I instead write the following standalone perl script:

#!/tool/bin/perl
use strict;

my $cmd = "myexecutable";

system($cmd);

my $exit_value = $? >> 8;
my $signal_num = $? & 127;
my $dumped_core = $? & 128;

printf("exit_value = $exit_value, signal_num = $signal_num, dumped_cor
+e = $dumped_core\n");
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The last line printed from the executable is:

right before out-of-bounds array access
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The values of the variables are as follows: exit_value = 0, signal_num = 11, dumped_core = 0 Why in this case is the "Segmentation fault" text not captured by the perl script? The behavior is the same if I replace this line:

system($cmd);
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my $backtick_return = `$cmd`;
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and then print $backtick_return at the end of the program. When I first started debugging this issue I was unaware of how to properly check system() return codes. Now that I've added that check as shown above debugging future issues should be easier, but I would still like to know why the "Segmentation fault" text isn't being captured by the system command, as seeing that when I first started debugging this issue would have been helpful.