Korn Shell Programming by Example

Command Interpretation Sequence

Understanding the way the shell interprets a command is an important debugging tool. The following sequence describes the order in which the shell interprets a line of your script:

1.	Process the following reserved words: {} esac select case fi then do for time done function until elif if while else in [[ ]]
2.	Process built-in commands: alias exit bg export return fg readonly trap kill typeset echo wait unalias print : unset read fc set cd getopts shift pwd let break times newgrp continue ulimit test eval umask whence exec jobs
3.	Search for functions on the command line.
4.	Search for aliases on the command line.
5.	Use the PATH variable to identify directories in which to look up programs/ scripts. ...