Difference between revisions of "Bash:Test"
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(Created page with "The test command evaluates an expression and sets $? 0 => True/Successful 1 => False/Unsuccessful In if statement test can be executed as [ expression ]. This has better read...") |
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| − | The test command evaluates an expression and sets $? 0 => True/Successful 1 => False/Unsuccessful | + | The test command evaluates an expression and sets $? |
| + | :0 => True/Successful | ||
| + | :1 => False/Unsuccessful | ||
| − | In if | + | In if statements test can be executed as [ expression ]. This has better readability. |
| + | |||
| + | ;if [ x${var} = x ] | ||
| + | :Test if var is empty | ||
| − | |||
;-f filename | ;-f filename | ||
:Regular file existence | :Regular file existence | ||
| Line 12: | Line 16: | ||
;-s filename | ;-s filename | ||
:File is bigger than 0 bytes | :File is bigger than 0 bytes | ||
| + | |||
| + | ;-z "string" | ||
| + | :String is zero-length | ||
| + | |||
| + | ;-n "string" | ||
| + | :String is not zero-length | ||
Latest revision as of 12:43, 11 May 2021
The test command evaluates an expression and sets $?
- 0 => True/Successful
- 1 => False/Unsuccessful
In if statements test can be executed as [ expression ]. This has better readability.
- if [ x${var} = x ]
- Test if var is empty
- -f filename
- Regular file existence
- -e filename
- Any file existence
- -s filename
- File is bigger than 0 bytes
- -z "string"
- String is zero-length
- -n "string"
- String is not zero-length