[dwm] OT: which or type or what else?

From: markus schnalke <meillo_AT_marmaro.de>
Date: Sat, 8 Dec 2007 21:40:52 +0100

Hoi community,

I have a question that is a bit off topic, but I think you are the
right ones to ask.

I'm writing some shell scripts these days, and a common task is to
check if a particular program is installed (for example `convert').

How is this check done in a sane and portable way?

The two alternatives that I have in mind are:

        which convert >/dev/null
        if [ $? -ne 0 ] ; then
                exit 1
        fi

and

        type convert >/dev/null
        if [ $? -ne 0 ] ; then
                exit 1
        fi

`type' is a builtin in `bash', but not in `sh'. Maybe it is available
as external program aswell.
Which systems do have `which'?

I want to cover most of the unixoid systems.
But I dont want to walk through $PATH.

meillo
Received on Sat Dec 08 2007 - 21:40:36 UTC

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