If you use a Unix system, and bash or sh as command interpreters (this does not work under csh), you can allways relay on system file descriptors and redirect them to /dev/null:

system "ls ~ &>/dev/null"; #Supress both stderr and stdout
system "ls ~ 2>/dev/null"; #Supress stderr
system "ls ~ 1>/dev/null"; #Supress stdout
[download]