4.10 Find All Command Versions with whereiz

To get the absolute pathname of a command, Korn shell users can run whence . bash users have type . On other shells, use which ( 50.8 ) . But those will only show the first directory in your PATH ( 6.4 ) with that command. If you want to find other commands with the same name in other directories, the standard which won't show them to you. (The which on the CD-ROM will - if you use its  - a option. So will the bash command type -all .) whereiz will:

% 

which grep

 /usr/bin/grep % 

whereiz grep

 /usr/bin/grep /usr/5bin/grep

On my system, the /usr/bin directory holds a Berkeley-like version of a command. The /usr/5bin directory holds System V versions. /usr/bin is first in my path, but it's good to know if there's also a System V version. whereiz also lets you see if there are both local and system versions of the same command in your path.

Here's the script. The name ends in a z because many UNIX versions already have a whereis ( 50.5 ) command.

&&

#! /bin/sh # COMMAND THAT TESTS FOR EXECUTABLE FILES... SYSTEM-DEPENDENT: testx="test -x" # REPLACE NULL FIELD IN $PATH WITH A . fixpath="`echo $PATH | sed \ -e 's/^:/.:/' \ -e 's/::/:.:/g' \ -e 's/:$/:./'`" IFS=": " # SET $IFS (COLON, SPACE, TAB) FOR PARSING $PATH for command do where="" # ZERO OUT $where # IF DIRECTORY HAS EXECUTABLE FILE, ADD IT TO LIST: for direc in $fixpath do $testx $direc/$command && where="$where $direc/$command" done case "$where" in ?*) echo $where ;; # IF CONTAINS SOMETHING, OUTPUT IT esac done

The sed ( 34.24 ) command "fixes" your PATH . It replaces a null directory name ( :: in the middle of the PATH or a single : at the start or end of the PATH ), which stands for the current directory. The null member is changed to the relative pathname for the current directory, a dot ( 1.21 ) , so the direc shell variable in the loop won't be empty. In line 12, the double quotes ( "" ) have colon, space, and tab characters between them. This sets the IFS ( 35.21 ) variable to split the "fixed" search path, at the colon characters, into separate directories during the for loop ( 44.16 ) . That's a useful way to handle any colon-separated list.