How to input STDIN

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I have a tool that can receive some parameters via system(...) but also needs (and waits for) some STDIN input that is needed. The program has no option to read this out of a file or to input via a parameter. Does there exist any way to automate this STDIN so the program does not wait for it or if it has to wait, to make that STDIN coming from a file or whatever? I hape I didnt confuse you. Thank you very much.

Comment on How to input STDIN

Replies are listed 'Best First'.
Re: How to input STDIN by friedo (Prior) on Dec 14, 2005 at 18:08 UTC
Check out Expect.	[reply]
Re^2: How to input STDIN by Celada (Monk) on Dec 14, 2005 at 21:51 UTC
Expect is overkill for this. Expect need only be used when there is interactice input AND output (you need to send something, wait for something, send something else...) or when the application is actually insisting that the input come from a tty. If the application will accept input on STDIN and all you want to do is feed it, you just need a pipe instead of `system`: `open(EXTERNAL, "\|your-command-goes-here with-its-arguments") or die; print EXTERNAL "The external program will receive this on STDIN\n"; close EXTERNAL;` [download] Some external commands ignore STDIN and go straight to the controlling tty to get their input because they want to guarantee that it comes from a user, not another program. `passwd` is typically one of them. That's when you need Expect.	[reply] [d/l] [select]
Re^3: How to input STDIN by Anonymous Monk on Dec 15, 2005 at 13:22 UTC
Tank you very... much	[reply]
Re^2: How to input STDIN by Anonymous Monk on Dec 14, 2005 at 20:32 UTC
Thank you but as I see Expect does not support ActivePerl. Does there exist any other method?	[reply]