action:Execute_a_Shell_Script
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| action:Execute_a_Shell_Script [2024/11/19 08:37] – peternlewis | action:Execute_a_Shell_Script [2025/09/12 07:02] (current) – [Quoting Strings] peternlewis | ||
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| * It is best to always specify the language using the `#!` at the front of the script. | * It is best to always specify the language using the `#!` at the front of the script. | ||
| * The script is executed with the `sh` shell, so if you want to use another language, or use any special kinds of shell-specific syntax, then you should specify the language. | * The script is executed with the `sh` shell, so if you want to use another language, or use any special kinds of shell-specific syntax, then you should specify the language. | ||
| - | * The shell is a non-login shell, so configuration files (like .bashrc) will not be run - in particular, this means you will not have much in the PATH (see below for more information). | + | * The shell is a non-login shell, so configuration files (like .bashrc) will not be run - in particular, this means you will not have much in the PATH (see [[# |
| * For more details and examples, see [[https:// | * For more details and examples, see [[https:// | ||
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| The tr command will replace `\r` or `\n` line endings with a nul character, and the `xargs -0` command will read that, split the arguments at the nul character, and pass them to the specified command (in this case `ls -l`. Note that xargs has a limit to the number of arguments it will pass, so for large numbers of arguments it may run the command multiple times with subsets of the arguments - read the `xargs` man page for more details. | The tr command will replace `\r` or `\n` line endings with a nul character, and the `xargs -0` command will read that, split the arguments at the nul character, and pass them to the specified command (in this case `ls -l`. Note that xargs has a limit to the number of arguments it will pass, so for large numbers of arguments it may run the command multiple times with subsets of the arguments - read the `xargs` man page for more details. | ||
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| + | Also note that shell globing happens after variable expansion, and so if the variable contains `*` characters they will be expanded by the shell by matching file names in the current directory. To avoid this, you can turn off globing by using the -f option when executing bash - that is, start your script with `# | ||
| ===== Path in Shell Scripts ===== | ===== Path in Shell Scripts ===== | ||
action/Execute_a_Shell_Script.1732005467.txt.gz · Last modified: by peternlewis