I have a driver written in perl that is used to call up an executable. My perl script asks two questions and reads from STDIN. The fortran executable posses several questions during run-time and reads from STDIN. The questions have to be where they are - they can't be moved, since they depend on what is going on in the code..

Everything works fine when I answers the questions manually. However, I would like to be able to pipe in an a text file containing the answers, to automate the process (Eg program.x < answers). This works well with a csh script, but not with the Perl one. The fortran program prints an end of file error, so it knows to read from STDIN, but there is nothing being passed. I think that the problem comes from the split read of STDIN, and all I need to do is pump the rest of the data in STDIN down to the executable.

Currently I am opening a temp file, reading the STDIN stream to it and then piping it into the executable in the system command. I don't really like this. 

 open(IN,">tmp.input");
 print IN <STDIN>;
 close(IN);
 $error = system("$runbin/$program.x < tmp.input");

[download]

Can anyone think of a cleverer way to use a pipe (or anything else) to redirect the rest of STDIN into the executable?

Stupid.

In reply to Split STDIN Pipe by murphya

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