sh(1): Document the special underscore parameter ("$_")

[0mp]

Summary

sh(1): Document the special underscore parameter ("$_")

[bcr]

Looks good to me.

[jilles]

Documentation for the _ variable was indeed missing.

bin/sh/sh.1

1329–1330

The character sequence _ is a name (per "Variables and Parameters" above), so this should be moved under "Special Variables" below.

The term "non-pipeline command" should be "simple command". This term is used elsewhere in the man page and is more precise. For example, a for loop which is a complex command that is not a pipeline still does not set $_ (except for any simple commands nested in it).

Also, it should be mentioned that $_ is only updated by interactive shells executing outside functions (if an interactive shell is currently executing a function, $_ expands to the last word of the last simple command executed before the outermost function call).

[0mp]

Adding rc to reviewers.

[pstef]

@0mp do you plan to work on this?

[0mp]

In D21571#724397, @pstef wrote:

@0mp do you plan to work on this?

@pstef, at some point, I hope so. Nevertheless, if you are willing to commandeer this revision then please do it by all means!