Just Curious: why do "/usr/bin/test" and "/usr/bin/[" have different sizes?
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A heads up about test, test and [ (yep, test is mentioned twice).
There is also a bash internal command called test, which is actually used when not using the full path to the test binary (/usr/bin/test). See man bash, the SHELL BUILTIN COMMANDS section.
The binary [ and binary test work the same way (except for the --version/--help), as you might have noticed both point to the saem manual page.
The binary and the build in do have some differences (availability and names of options).
The reason test does not recognise any options is that it would not be possible to distinguish whether the option was actual option or a test. I.e. “test "$FOO"” is a valid way to test whether the variable FOO is empty or not, however if FOO was “--help” or “--version”, the test would result in superfluous output.
[ can support options since its valid invocation requires “]” at the end of the command.
Quote:
Originally Posted by druuna
There is also a bash internal command called test, which is actually used when not using the full path to the test binary (/usr/bin/test). See man bash, the SHELL BUILTIN COMMANDS section.
There is also a bash built-in “[” (which does not support “--help” or “--version” by the way).
PS. This of course does not change the fact that both binaries could be the same and the behaviour could be changed based on “argv[0]”. I assume this is not the cases to speed things up slightly.
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