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use a literal bang (exclamation point) in a command

Terminal - use a literal bang (exclamation point) in a command
echo '!'whammy
2009-03-26 23:34:33
User: sudopeople
Functions: echo
-3
use a literal bang (exclamation point) in a command

Seems obvious, but other seemingly simple ways to use it don't work:

echo !whammy

and

echo "!whammy"

both output:

-bash: !whammy: event not found

and this:

echo "\!whammy"

outputs:

\!whammy

with the slash :(

you can also do any combinations of quotes for a complex string:

echo "It's great to be able to use a bang ("'!'") in a command"'!'

outputs:

It's great to be able to use a bang (!) in a command!

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

Two other simple solutions:

1. Escape it, but don't put it in double quotes:

echo \!whammy

2. Put the whole thing in single quotes:

echo '!whammy'
Comment by bjimba 295 weeks and 2 days ago

While we're doing neat echo tricks, here's another:

doing multi-line echos:

echo "hello

world"

will fail, resulting in [ hello world ]

but doing

echo 'hello

world'

will result in [ hello

world ]

as expected.

Comment by clockworkavian 295 weeks and 2 days ago

clockworkavian Both of your commands shown do *exactly* what is expected. Single quotes prevent the shell from expanding, modifying, or interpreting the data given to it. Double quotes, or interpolating quotes, do not.

Comment by ozymandias 295 weeks and 2 days ago

@bjimba:

Didn't know about #1 thanks\! :)

and #2 is implied in my examples, I chose to separate the bang into its own single quotes to emphasize their use (I assume most people use none quotes or double quotes normally, like me.)

I don't know why I tend to use double quotes at the shell. Coming from a PHP background, I use single quotes 99% of the time elsewhere.

@ozymandias:

Thanks for the info, I wish I would have know that all along.

It's very similar to the difference between single and doubt quotes in PHP. I'm surprised I didn't make the connection earlier. Makes me glad I posted this one. I learned a lot :)

Comment by sudopeople 295 weeks and 2 days ago

Your point of view

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