Linux Shell Scripting Cookbook - Third Edition

Showing environment variables for a process

Some processes are dependent on their environment variable definitions. Knowing the environment variables and values can help you debug or customize a process.

The ps command does not normally show the environment information of a command. The e output modifier at the end of the command adds this information to the output:

$ ps e

Here's an example of environment information:

$ ps -eo pid,cmd  e | tail -n 1
1238 -bash USER=slynux LOGNAME=slynux HOME=/home/slynux PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
MAIL=/var/mail/slynux SHELL=/bin/bash SSH_CLIENT=10.211.55.2 49277 22 SSH_CONNECTION=10.211.55.2 49277 10.211.55.4 22 SSH_TTY=/dev/pts/0 

Environment information helps trace ...