0001637: The command utility does not execute aliases

Notes
(0006180) kre (reporter) 2023-02-27 18:55	Yet another case where we would be far better off if the standard had no aliases. No surprise that no shells do what the text kind of looks like it expects, as aliases would have been processed long before the "command" command is executed - if one wanted to have "command" apply to aliases (alias values) as well, one could do alias command='command ' which would expand a following alias after command (as part of lexical processing) if one appears there. Without that, "command" is the word in the command word position, if that is not an alias, no further words get checked to see if they are, until the next command word position (which the following word is not, nor is it in "exec word", xargs word, env word, ... though it can be in "eval word" as that word is subject to lexical processing (to be tokenised). The desired action is not adequate however, as it gives no clue what should happen in the case in question. When the word after "command" is a function, earlier text says what happens, but nothing does if it is an alias. However, I agree that as long as aliases remain in POSIX, the text there needs to be clearer. I'd suggest something more like adding to the end of the sentence in question except that command_word does not appear in the command word position in the command command, hence is not subject to alias or reserved word lookups. Note that command also suppresses reserved words, "command if ..." runs the "if" command (from the filesystem, since command suppresses function lookups, a function named "if" can't be run this way, even in shells that allow it to be defined). eg: $ cat $HOME/bin/if #! /bin/sh echo If Only. $ command if args are ignored in that script If Only. Every shell I tested behaves like that, as they all should.

(0006203) geoffclare (manager) 2023-03-13 15:52 edited on: 2023-03-13 15:56	After: If the command_name is the same as the name of one of the special built-in utilities, the special properties in the enumerated list at the beginning of Section 2.14 (on page 2384) shall not occur. In every other respect, if command_name is not the name of a function, the effect of command (with no options) shall be the same as omitting command . add: , except that command_name does not appear in the command word position in the command command, and consequently is not subject to alias substitution (see [xref to 2.3.1]) nor recognized as a reserved word (see [xref to 2.4]).

Issue History
Date Modified	Username	Field	Change
2023-02-27 17:17	nick	New Issue
2023-02-27 17:17	nick	Name	=> Nick Stoughton
2023-02-27 17:17	nick	Organization	=> Logitech
2023-02-27 17:17	nick	Section	=> command
2023-02-27 17:17	nick	Page Number	=> 2596
2023-02-27 17:17	nick	Line Number	=> 84263-84266
2023-02-27 17:17	nick	Interp Status	=> ---
2023-02-27 17:17	nick	Category	System Interfaces => Shell and Utilities
2023-02-27 18:55	kre	Note Added: 0006180
2023-03-13 15:52	geoffclare	Note Added: 0006203
2023-03-13 15:53	geoffclare	Final Accepted Text	=> Note: 0006203
2023-03-13 15:53	geoffclare	Status	New => Resolved
2023-03-13 15:53	geoffclare	Resolution	Open => Accepted As Marked
2023-03-13 15:53	geoffclare	Tag Attached: tc3-2008
2023-03-13 15:56	geoffclare	Note Edited: 0006203
2023-05-16 11:04	geoffclare	Status	Resolved => Applied
2023-05-16 11:04	geoffclare	Tag Attached: applied_after_i8d3
2024-06-11 09:07	agadmin	Status	Applied => Closed

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