which-2.16 and alternatives

The presence or absence of the which program in the main LFS book is probably one of the most contentious issues we have on the mailing lists. It has resulted in at least one flame war in the past. To hopefully put an end to this once and for all, we here present two of the options for equipping your system with "which". The question of which "which" is for you to decide.

The first option is to install the actual GNU program which.

Introduction to which

Package information

Download (HTTP): http://www.xs4all.nl/~carlo17/which/which-2.16.tar.gz
Download (FTP): ftp://ftp.gnu.org/gnu/which/which-2.16.tar.gz
Download size: 123 KB
Estimated Disk space required: 940 KB
Estimated build time: 0.03 SBU

Installation of which

Install which by running the following commands:

./configure --prefix=/usr &&
make &&
make install

The which package contains which.

Description

which

which shows the full path of (shell) commands.

The 'which' script

The second option (for those who don't want to install the program) is to create a simple script:

cat > /usr/bin/which << "EOF"
#!/bin/bash
type -pa "$@" | head -n 1 ; exit ${PIPESTATUS[0]}
EOF
chmod 755 /usr/bin/which
chown root:root /usr/bin/which

This should work OK and is probably the easiest solution for most cases, but is not the most comprehensive implementation.