Bash - Source - Built-in command

About

source is a built-in command that executes a script with the namespace scope of the caller.

The point . is an alias.

It will:

• read and execute commands from filename in the current shell environment
• return the exit status of the last command executed from filename.

The return status is the status of the last command exited within the script (0 if no commands are executed), and false if filename is not found or cannot be read.

Example

source .bash_profile

is the same as

. .bash_profile

Syntax

.      filename [arguments]
source filename [arguments]

where:

• arguments are the arguments (ie positional parameters.
  • If any arguments are supplied, they become the positional parameters when filename is executed.
  • Otherwise the positional parameters are unchanged.
• filename is the file to execute.
  • If filename does not contain a slash, file names in the PATH environment variable are used to find the name of a not executable file.
  • When bash is not in posix mode, the current directory is searched if no file is found in PATH.