As Utilitarian said, it would help if you show your code, and also show the specific error message(s) or other evidence you have that shows exactly what "not working" really means.

And really, if it's just a matter of making it easier to run two processes in sequence without having to wait, using perl for that is overkill. If you just save the two command lines (or a single conjoined command line as suggested in my first reply) as a plain text file, you can "run" that file as a shell script:

source my_shell_script
[download]

. my_shell_script
[download]

$ perl -Mstrict -e 'my @out =qx{ls $ENV{HOME}/tmp}; 
chomp @out;
print join (", " , @out), "\n";'
a.out, test.c, test.dat, test.pl
[download]

OK there was syntax problem i was able to run the command. But here comes another problem. The first command here creates the an environment, in that environment i need to execute the second command. Here nither system nor exec will do these. Untill I manually exit from environment the second command is not running. Once i exit from environment the second executes. But i need the second command to be executed in environment which was set by first command. Is it possible to do so? Please help!!!!

See Get default login environment.

You could try something like:

#!/usr/bin/perl

use strict;

my $shpid = open( SH, '|-', '/bin/bash' ) or die "Can't launch bash: $
+!\n";

my @command_list = ( 
   "first_command args ...\n",
   "second_command args ...\n"
   ... );

for my $cmd ( @command_list ) {
    print SH $cmd;
}
print SH "exit\n";
waitpid( $shpid, 0 );
[download]

If the list of commands actually includes things that change the shell environment for subsequent commands, that should work as intended.