You can also use exec(), or the open or open2 methods of IPC::Open2, or even open3 of IPC::Open3 if you want finer control of input and output.

exec will start the other program, terminating your perl program.

open lets you either read or write from/to the process.

open2 lets you do both, but isn't very portable.

open3 lets you read from both STDOUT and STDERR, and write to STDIN, but it can get ugly trying to read both outputs. It also has the portability problems of open2.