November 2015
Beginner
282 pages
5h 5m
English
The shell builtin command test can be used to check file types and compare expressions value. The syntax is test EXPRESSION or the test command is also equivalent to [ EXPRESSION ].
It returns the exit code 1 (false) if the EXPRESSION result is 0, and 0 (true) for a non-zero EXPRESSION result.
If no EXPRESSION is provided, the exit status is set to 1 (false).
Different kinds of checks can be done on the file using the test command; for example, file existence test, directory test, regular file check, symbolic link check, and so on.
The options available to do various checks on a file are explained in the following table:
|
Option |
Description |
|---|---|
|
-e |
fileChecks whether the file exists |
|
-f file |
The file is a regular ... |