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Old 06-05-2011, 01:35 PM   #1
stf92
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Does 'time' run the internal time command or the external one?


Hi:

For some shell built-in commands there are external commands with the same name and identical or nearly identical behaviour (they do the same thing). Suppose foo is such a name. What does this do?
Code:
$ foo
Runs the internal or external command? Thanks.
 
Old 06-05-2011, 01:56 PM   #2
druuna
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Hi,

When bash executes the command it looks for it in this order:

1 - alias,
2 - keyword,
3 - function,
4 - built-in,
5 - executable (external).

If foo is an alias, function and executable name, the alias will be executed.

Hope this helps.

EDIT:

Run: command -V <command> to check which is used.

Last edited by druuna; 06-05-2011 at 02:05 PM. Reason: Added command -V
 
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Old 06-05-2011, 02:38 PM   #3
stf92
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Hi:

I typed 'command -V time' and was said 'time is a shell keyword'. I had looked (bash man) under SHELL BUILTIN COMMANDS and did not find time. The only place I found it was in the definition of pipeline. Which now makes very good sense. Thanks for the list.

Last edited by stf92; 06-05-2011 at 08:02 PM.
 
Old 06-05-2011, 02:56 PM   #4
druuna
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Hi,

help time also gives some information, although the pipeline section in man bash is better (my 2c).

Hope this helps.
 
Old 06-05-2011, 08:19 PM   #5
stf92
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Thanks a lot, druuna, and kind regards.

Quote:
Originally Posted by druuna View Post
Hi,

help time also gives some information, although the pipeline section in man bash is better (my 2c).

Hope this helps.
Out of sheer curiosity: what does 2c stand for? Anything to do with bash version number?

Last edited by stf92; 06-05-2011 at 08:22 PM.
 
Old 06-06-2011, 02:20 AM   #6
chrism01
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2c = 2 cents ..
YCMV (Your Currency May Vary)
 
Old 06-06-2011, 03:04 AM   #7
stf92
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Thanks chrism01. That is the bad fortune with non-native English speakers in an English speaking forum. Everything has to be explained to us (and everything IS explained). Although there are native speakers who speak English very well. Not my case.

Now, I'll write in a linguistics forum to understand what druuna meant by his two cents.
 
Old 06-06-2011, 03:55 AM   #8
druuna
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Hi,

Sorry I confused you, I thought this one was well known in the on-line community.

This is what Wiki has to say about this one: My two cents
 
Old 06-06-2011, 05:11 AM   #9
stf92
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Getting into Wiki was the first thing I did. But I missed the expression. An innocent idiom and one is lost. What a patience on the part of you guys.
 
  


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