This is an issue i face long back. So i guess you should put the shell commands in a file like a.sh and invoke that from perl. To analyse the problem further if you could check the ps -ef and figure out how the process is carried.. Do let me know if it works. Try using system or exec and one of them should help ... I guess i used something like open (HANDLE,"ls -altr|grep abc|awk -F '{print NF}'|");