I am experimenting with using the fork and exec functions to spawn a child process and execute a different script. My ultimate goal is to spawn multiple child processes from the parent without waiting for any of the children to complete. My first attempt is to merely spawn a single child. The parent code is as follows: 

#!/usr/bin/perl

use strict;
use warnings;

my $pid;

if( $pid = fork ){
    print "In test1 the parent pid is $$; the child pid is $pid\n";
} else {
    die "could not fork a process: $!" unless defined $pid;
    exec ( "/liwidata/dev/tmp/jmg/dev/library/test2.pl" ) or print STD
+ERR "couldn't exec test program: $!";
}

print "All done!\n";

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The child code is as follows: 

#!/usr/bin/perl

use strict;
use warnings;

print "In test2.pl the pid is $$\n";

[download]

When I execute the parent script I receive the following output: 

/liwidata/dev/tmp/jmg/dev/library> ./test1.pl
In test1 the parent pid is 21348; the child pid is 21349
All done!
/liwidata/dev/tmp/jmg/dev/library> In test2.pl the pid is 21349

[download]

As you can see the command prompt does not appear at the conclusion of the child script. I must enter a Ctrl-C in order to get it back. What am I doing wrong?

In reply to exec function does not return command prompt by casman46

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