On Mon, Dec 23, 2024 at 20:37:38 -0500, Jeffrey Walton wrote: > On Mon, Dec 23, 2024 at 8:32 PM George at Clug <c...@goproject.info> wrote: > > Is this the main point to command? "will execute the external command ls > > instead of calling the function recursively"
Like many shell builtins, "command" does multiple things, depending on how you use it. Suppressing function lookups is certainly *one* of the things it does. Printing the first path of an external command is another things that it does. I already showed an example of a wrapper function that uses "command ls" to run the external command instead of the function. > Greg provided the link to the documentation: > > The "command" command's base functionality is specified by POSIX: > <https://pubs.opengroup.org/onlinepubs/9799919799/utilities/command.html> > > And following the link: > > DESCRIPTION > > The command utility shall cause the shell to treat the arguments as a > simple command, suppressing the shell function lookup that is described > in 2.9.1.4 Command Search and Execution, item 1c. And also: When the -v or -V option is used, the command utility shall provide information concerning how a command name is interpreted by the shell. That feature is used when you want to determine whether something is already installed. hobbit:~$ if command -v firefox-esr >/dev/null; then echo firefox installed; fi firefox installed hobbit:~$ if command -v emacs >/dev/null; then echo emacs installed; fi hobbit:~$ Obviously that's more useful in a script. If you're a human and you just want that information for your own curiosity, "type" is a lot easier to use: hobbit:~$ type firefox-esr firefox-esr is /usr/bin/firefox-esr hobbit:~$ type emacs bash: type: emacs: not found
