What is it “!!” and how it connected to `$_` or `$?`?
I was playing with string substitution while learning a bit more of bash, and I have add !! into some dummy example echo ${TEST/hey/!!}...
I was surprised that !! was replaced with last entered command... what is it? is it somehow connected to magick codes link $? or $_ or even -. Is there anything else I can use in same manner in bash?
bash
asked 8 mins ago
Butuzov
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I was playing with string substitution while learning a bit more of bash, and I have add !! into some dummy example echo ${TEST/hey/!!}...
I was surprised that !! was replaced with last entered command... what is it? is it somehow connected to magick codes link $? or $_ or even -. Is there anything else I can use in same manner in bash?
bash
asked 8 mins ago
Butuzov
1011
New contributor
Butuzov is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
1
Related (but doesn’t address the relationship with parameter expansion): Understanding the exclamation mark (!) in bash.
– Stephen Kitt
6 mins ago
add a comment |
I was playing with string substitution while learning a bit more of bash, and I have add !! into some dummy example echo ${TEST/hey/!!}...
I was surprised that !! was replaced with last entered command... what is it? is it somehow connected to magick codes link $? or $_ or even -. Is there anything else I can use in same manner in bash?
bash
asked 8 mins ago
Butuzov
1011
New contributor
Butuzov is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I was playing with string substitution while learning a bit more of bash, and I have add !! into some dummy example echo ${TEST/hey/!!}...
I was surprised that !! was replaced with last entered command... what is it? is it somehow connected to magick codes link $? or $_ or even -. Is there anything else I can use in same manner in bash?
bash
bash
asked 8 mins ago
Butuzov
1011
New contributor
Butuzov is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 8 mins ago
Butuzov
1011
New contributor
Butuzov is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 8 mins ago
Butuzov
1011
New contributor
Butuzov is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 8 mins ago
Butuzov
1011
asked 8 mins ago
Butuzov
1011
1011
New contributor
Butuzov is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Butuzov is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Butuzov is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
1
Related (but doesn’t address the relationship with parameter expansion): Understanding the exclamation mark (!) in bash.
– Stephen Kitt
6 mins ago
add a comment |
1
Related (but doesn’t address the relationship with parameter expansion): Understanding the exclamation mark (!) in bash.
– Stephen Kitt
6 mins ago
1
1
Related (but doesn’t address the relationship with parameter expansion): Understanding the exclamation mark (!) in bash.
– Stephen Kitt
6 mins ago
Related (but doesn’t address the relationship with parameter expansion): Understanding the exclamation mark (!) in bash.
– Stephen Kitt
6 mins ago
add a comment |
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1
Related (but doesn’t address the relationship with parameter expansion): Understanding the exclamation mark (!) in bash.
– Stephen Kitt
6 mins ago