Providing Input to an executable that is invoked from perl script

[prasannakiran]

Hi,
I am new to perl and need help in the below situation

I have a C language executable called myprogram and i am calling it from my perl script test.pl.My OS is linux.
below is the code for test.pl

_______________________________________________________

#!/usr/local/bin/perl
$command = "make";
system("$command");
chdir("/mydir");
$command = "./myprogram";
system("$command");

_________________________________________________________

here the executable myprogram is an interactive program.
When i run, it asks to enter the user name first and then regristration number.So when i try to execute from the perl script, it is running fine and asking the user input.At present i am giving it manually..But i have to automate that process also..I am not getting how to provide input to that through perl script...Any help??

Thanks in Advance
PK

 

[Mike042]

Input to a Perl script can usually come from one (or more) of three sources:
- input from the keyboard
- parameters passed to the script (via @ARGV) - data or names of files
- information by reading files

It is also possible to write the script so that if information is not present where it is expected then another source is used (or prompted for).

I hope that helps.

Mike

 

[prasannakiran]

Mike,
my question is my script test.pl should provide input to the interactive program myprogram.When myprogram is running, the input should be provided by a perl script..

 

[KevinADC]

Check if your program accepts command line arguments. Many programs have options for providing input from the command line or switches that can be set to automate processes like you are trying to do.

- Kevin, perl coder unexceptional!

 

[rharsh]

Since you're running on a *nix environment, you might want to look into Expect.pm and/or Expect::Simple for your automated input.

 

[stevexff]

If myprogram reads from STDIN, you can pipe the input in to the command. Maybe write a temp file from perl with the commands in it, then

system('./mycmd < tempfile.txt');

or even

my @results = qx{./mycmd < tempfile.txt};

if you need to capture the output.

Steve

[small]"Every program can be reduced by one instruction, and every program has at least one bug. Therefore, any program can be reduced to one instruction which doesn't work." (Object:erlDesignPatterns)[/small]