Bash set

External

• set man page http://linuxcommand.org/lc3_man_pages/seth.html
• https://www.gnu.org/software/bash/manual/html_node/The-Set-Builtin.html

Internal

• bash

set and Positional Parameters

arg="a b c"
set - ${arg}

assigns "a", "b", "c" to positional parameters $1, $2 and $3. '-' that follows the builtin signals the end of options and causes all remaining arguments to be assigned to the positional parameters. This prevents arguments that start with "--..." to interfere with set function. If "-" is not specified, and the first of the space-separated arguments contains '--', set will try to interpret that sequence of characters and will produce:

set: --: invalid option

List Separator

The default list separator is space. That can be changed by setting the value of the IFS variable before executing set.

Example:

arg="a,b,c"
IFS=","
set ${arg}

will identically assign "a", "b", "c" to positional parameters $1, $2 and $3.

Note you must set IFS back to whitespace after setting it to something else, so the basic shell function work as expected. This is done as shown here: restoring the default IFS value.

For more details about IFS see: