Re: Finding commands in Unix PATH

Zsh keeps a hash of all commands in PATH (updated when you run hash -r and/or twiddle PATH) in a parameter.

$ for i in ${(onk)commands}; [[ "$i" == *grep* ]] && print $i
bzegrep
bzfgrep
bzgrep
egrep
fgrep
git-grep
grep
grep-changelog
msggrep
pcregrep
podgrep
tcgrep
xml_grep
zegrep
zfgrep
zgrep
zipgrep
[download]

Granted that's a zsh pattern not a regexp (however if you really want to you can compile in pcre support when you build zsh :). Functionalization left as an exercise for the reader.

Update: Ooop, note that that's run with setopt short_loops; without that you'd need the usual shell-y do ... done around the body.

The cake is a lie.
The cake is a lie.
The cake is a lie.

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Re^2: Finding commands in Unix PATH by jdporter (Paladin) on Jun 05, 2008 at 13:50 UTC
`perl -le "/grep/ and print for @ARGV" ${(onk)commands}` [download] whatever `${(onk)commands}` is/does. I'm not familiar with the peculiarities zsh.	[reply] [d/l] [select]
Re^3: Finding commands in Unix PATH by Fletch (Bishop) on Jun 05, 2008 at 14:00 UTC
Zsh has several flags that affect parameter expansion. The `k` flag says to expand a hash into a list of its keys (rather than the default which is to expand into a list of its values; or you index it like `${commands[ls]}` and get the path to `ls`). The `o` flag says to sort the resulting expansion by name in ascending order (the `on` is actually wrong but works; I was confuzzling glob expansion qualifiers where it's `oX` where X specifies what to sort on (e.g. `n` for filename, or `m` for modification time)). So Perl's in a run for its money with regards to line-noisy-ness compared to terse zsh. :) The cake is a lie. The cake is a lie. The cake is a lie.	[reply]