The source
command is used to read and execute commands from a specified file within the current shell environment. The file can contain any valid shell commands, including variable assignments, function definitions, and other executable statements.
The syntax for using source
is as follows:
source filename
or
. filename
Both commands are equivalent, with the latter being a shorthand notation for the former.
When executed, the contents of the specified file are read and executed as if they were typed directly into the current shell environment. This means that any changes to environment variables, aliases, or other shell settings made within the file will persist after the file has been executed.
Examples
Here are some examples of how to use the source
command:
- To execute a script named
myscript.sh
in the current shell environment:
source myscript.sh
- To execute a script named
myscript.sh
using the shorthand notation:
. myscript.sh
- To execute a script located in a different directory:
source /path/to/myscript.sh
- To execute a script with a relative path:
source ./myscript.sh
Options
The source
command does not have any options.
Troubleshooting Tips
- If you receive an error message stating that the specified file cannot be found, verify that the file exists and that you have permission to read it.
- If the file contains syntax errors or other issues, you may receive error messages when executing the
source
command. Review the contents of the file to identify and correct any issues.
Notes
- The
source
command is often used in shell scripts to load configuration files or other scripts into the current shell environment. - The
.
notation for thesource
command is a shorthand notation that is commonly used in shell scripts for brevity.