Eliminating Stdout and Stderr of Program Receiving EOF Input

MrName · 06-04-2013, 04:07 PM

Hello all, first time posting here, but spent a lot of time reading the forums. Right now, I am working on a BASH script in which a program is being called, and receiving input via EOF redirection, like so:

Code:

/usr/bin/program << EOF

.....data.....

EOF

This is working just fine, but I want to make the output silent. No matter where I append '> /dev/null 2>&1' I cannot get rid of the stdout or stderr of the actual program being called. It generally causes an error, or has no effect. Is there a way to properly redirect the stdout/stderr of this program? I have tried every possible combination. Any help is greatly appreciated! Thank you!

David the H. · 06-04-2013, 04:14 PM

It should work like this:

Code:

/usr/bin/program << EOF >/dev/null 2>&1

.....data.....

EOF

The program has three redirections defined for it. stdin is the heredoc, stdout is /dev/null, and stderr is set to the same place as stdout, also /dev/null.

If that doesn't work for you, and I can't see how it wouldn't, please show us what it's really doing in more detail.

Another possibility is to wrap the whole thing in a program group, function, or subshell and redirect that.

Code:

{
/usr/bin/program << EOF

.....data.....

EOF
} >/dev/null 2>&1

Edit: see here for more on how redirections work:
redirections and file descriptors explained

MrName · 06-04-2013, 04:19 PM

Dude, that was amazingly fast, and a great explanation! Trying right now, and will update this thread. Thank you very much.

MrName · 06-04-2013, 04:22 PM

Answer 1 worked like a charm! Thank you very much, not sure how I missed that. You rock!