rexec and child processes in Perl

[BenP]

I'm trying to write a Perl script that runs a SAS program on a remote server with user-input parameters from an HTML form. If the SAS program completes quickly enough, I want the results returned as HTML in real time; otherwise I want to display a message and email the user with the results when the SAS program finishes.

I'm trying to fork off a child to make a system call for rexec to run the SAS program, and have the parent wait for either a timeout or a completed program. But it seems like the child doesn't even run the rexec line. It immediately returns -1. Apparently Net::SSH isn't installed so I can't use that instead. I can successfully FTP a SAS config file from the HTML form in the child process.

Any advice on what I might be doing wrong with rexec? It works fine if it's not called in the child. It also works if I run the same command in the command line.

[RobUSVI]

A bit beyond my comfort zone, but the first things I would check are execution path and permissions (of the to be exed'd process) on the remote side.

[ShadowOfGed]

I'm not familiar with anything called "rexec." Can you explain that a bit further?

[BenP]

I'm not familiar with anything called "rexec." Can you explain that a bit further?

Same as exec but can run commands on a remote server, and has options for a username and password.

http://www.rt.com/man/rexec.1.html

[Taskiss]

The only thing I can suggest is to make sure you can start the process via cron or at or something like that, to make sure it can execute without having a terminal attached to the process. I've run into situations where the app requires a TERM variable set and it isn't set automatically in some cases.

Once you can get it to run via cron, you should be able to fire it up from anything.

[ShadowOfGed]

What process/web server are you forking FROM? And what platform are you on? There are a host of things that can go wrong during the fork/exec process (presuming you're calling exec in some form). The -1 probably indicates your fork/exec never really got off the ground.