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Posted on 1998-02-19
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UNIXer,

What is the usage of "!" ??????

Andrew
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Question by:andrewyu
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by:ozo
ID: 2008822
In what context?
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rams021898 earned 0 total points
ID: 2008823
a) In the sed utility, the "!" is used to match all lines not cvoered in the address.

b) In the awk utility, the "!" is the negation operator.

c) When you type "history", you will get your history list of commands.  Typing "!" and a number will execute that specific command.

or even

d)In ftp, the "!" command tells ftp that you want to run a shell comman on your local host (like "!ls").

I think that's most, if not all of its uses.

Hope this helped....
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by:ahoffmann
ID: 2008824
In a couple of apps (rams still mentioned ftp) it is the shell escape (ex, ed, vi, etc.).
rams, in c) you asume csh, tcsh or something similar ;-)

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by:braveheart
ID: 2008825
! is also often a history operator in debuggers and similar applications. In the csh, it is also a negation operator. I'll bet that we haven't exhausted all the possibilities yet.
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