Usage of enclosing braces {} as arguments to commands and their options
Examples
I've recently found examples of using pairs of enclosing braces {}, with nothing in between the opening and closing braces, as arguments to commands and even to their options:
cat foo | xargs -I{} echo {}
find . -size 0 -exec rm -i {} ;
No Documentation
My problem is that I cannot find a documentation in the GNU Bash Manual that describes the usage of {} in such context as in the examples above.
I do not think it is a parameter expansion, because a dollar sign must precede the enclosing braces in a parameter expansion as in ${}.
It cannot be a brace expansion either, because it takes the form of {x..y[..incr]}, where x and y are not optional.
It also cannot be a command grouping either, because {} is used as arguments.
Questions
What does a pair of enclosing braces
{}even mean, in general, as an argument to any command that accepts it?Where can I find a documentation that describes the usage of
{}as arguments?
bash shell
asked 4 mins ago
Niko GambtNiko Gambt
1
New contributor
Niko Gambt is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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add a comment |
Examples
I've recently found examples of using pairs of enclosing braces {}, with nothing in between the opening and closing braces, as arguments to commands and even to their options:
cat foo | xargs -I{} echo {}
find . -size 0 -exec rm -i {} ;
No Documentation
My problem is that I cannot find a documentation in the GNU Bash Manual that describes the usage of {} in such context as in the examples above.
I do not think it is a parameter expansion, because a dollar sign must precede the enclosing braces in a parameter expansion as in ${}.
It cannot be a brace expansion either, because it takes the form of {x..y[..incr]}, where x and y are not optional.
It also cannot be a command grouping either, because {} is used as arguments.
Questions
What does a pair of enclosing braces
{}even mean, in general, as an argument to any command that accepts it?Where can I find a documentation that describes the usage of
{}as arguments?
bash shell
asked 4 mins ago
Niko GambtNiko Gambt
1
New contributor
Niko Gambt is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Some commands have this options{}- meaningtargetsto act on, withfindcommand, it's remove/rmfound files.
– Tuyen Pham
25 secs ago
add a comment |
Examples
I've recently found examples of using pairs of enclosing braces {}, with nothing in between the opening and closing braces, as arguments to commands and even to their options:
cat foo | xargs -I{} echo {}
find . -size 0 -exec rm -i {} ;
No Documentation
My problem is that I cannot find a documentation in the GNU Bash Manual that describes the usage of {} in such context as in the examples above.
I do not think it is a parameter expansion, because a dollar sign must precede the enclosing braces in a parameter expansion as in ${}.
It cannot be a brace expansion either, because it takes the form of {x..y[..incr]}, where x and y are not optional.
It also cannot be a command grouping either, because {} is used as arguments.
Questions
What does a pair of enclosing braces
{}even mean, in general, as an argument to any command that accepts it?Where can I find a documentation that describes the usage of
{}as arguments?
bash shell
asked 4 mins ago
Niko GambtNiko Gambt
1
New contributor
Niko Gambt is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Examples
I've recently found examples of using pairs of enclosing braces {}, with nothing in between the opening and closing braces, as arguments to commands and even to their options:
cat foo | xargs -I{} echo {}
find . -size 0 -exec rm -i {} ;
No Documentation
My problem is that I cannot find a documentation in the GNU Bash Manual that describes the usage of {} in such context as in the examples above.
I do not think it is a parameter expansion, because a dollar sign must precede the enclosing braces in a parameter expansion as in ${}.
It cannot be a brace expansion either, because it takes the form of {x..y[..incr]}, where x and y are not optional.
It also cannot be a command grouping either, because {} is used as arguments.
Questions
What does a pair of enclosing braces
{}even mean, in general, as an argument to any command that accepts it?Where can I find a documentation that describes the usage of
{}as arguments?
bash shell
bash shell
asked 4 mins ago
Niko GambtNiko Gambt
1
New contributor
Niko Gambt is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 4 mins ago
Niko GambtNiko Gambt
1
New contributor
Niko Gambt is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 4 mins ago
Niko GambtNiko Gambt
1
New contributor
Niko Gambt is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 4 mins ago
Niko GambtNiko Gambt
1
asked 4 mins ago
Niko GambtNiko Gambt
1
1
New contributor
Niko Gambt is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Niko Gambt is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Niko Gambt is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Some commands have this options{}- meaningtargetsto act on, withfindcommand, it's remove/rmfound files.
– Tuyen Pham
25 secs ago
add a comment |
Some commands have this options{}- meaningtargetsto act on, withfindcommand, it's remove/rmfound files.
– Tuyen Pham
25 secs ago
Some commands have this options
{} - meaning targets to act on, with find command, it's remove/rm found files.– Tuyen Pham
25 secs ago
Some commands have this options
{} - meaning targets to act on, with find command, it's remove/rm found files.– Tuyen Pham
25 secs ago
add a comment |
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Some commands have this options
{}- meaningtargetsto act on, withfindcommand, it's remove/rmfound files.– Tuyen Pham
25 secs ago