The command(1) shell built-in executes command_name
as if it had been given from the command line, with two exceptions.
First, command_name cannot be a shell function, and second,
special built-in commands lose their specialness (that is,
redirection and utility errors do not cause the shell to exit, and
command assignments are not permanent). This makes
command(1) useful for stepping around shell functions that
have already been defined.
Use a default search path (the output of getconf
CS_PATH) instead of the current PATH
Like -v, but verbose.
Instead of executing command_name, display information
about the command that would be executed. For special and regular
built-in commands and functions, command(1) prints their
names; for aliases, it prints the command that defines them, and
for commands found by searching the PATH parameter, it
prints the full path of the command. If no command is be found,
(that is, the path search fails), nothing is printed and
command(1) exits with a non-zero status.