I've tried to find an answer to this problem but It seems like there is something which I do not quite understand:

I have a script in which dumps a lot of output to the shell. When I do use the ampersand (&) to run the script as a background process it still prints the same output to the shell. So my questions is: Is it possible for the script to know that it has been put in the background by ampersand so that it can silence itself (re-direct STDOUT/STDERR TO /dev/null)?

Update: Thanks everyone for great feedback. I got what I was looking for and I ended up with a check that was in almuts link: 

    171 if (!open(TTY, "/dev/tty")) {
    172     print "no tty\n";
    173 } else {
    174     my $tpgrp = tcgetpgrp(fileno(*TTY));
    175     my $pgrp = getpgrp();
    176     if ($tpgrp == $pgrp) {
    177         print "foreground\n";
    178     } else {
    179         print "background\n";
    180     }
    181 }

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In reply to How to know if a perl script is put in the background by rapide

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