Save modifications in place with awk
In GNU Awk 4.1.0 (released 2013) and later, it has the option of "inplace" file editing:
[...] The "inplace" extension, built using the new facility, can be used to simulate the GNU "
sed -i
" feature. [...]
Example usage:
$ gawk -i inplace '{ gsub(/foo/, "bar") }; { print }' file1 file2 file3
To keep the backup:
$ gawk -i inplace -v INPLACE_SUFFIX=.bak '{ gsub(/foo/, "bar") }
> { print }' file1 file2 file3
Unless you have GNU awk 4.1.0 or later...
You won't have such an option as sed's -i
option so instead do:
$ awk '{print $0}' file > tmp && mv tmp file
Note: the -i
is not magic, it is also creating a temporary file sed
just handles it for you.
As of GNU awk 4.1.0...
GNU awk
added this functionality in version 4.1.0 (released 10/05/2013). It is not as straight forwards as just giving the -i
option as described in the released notes:
The new -i option (from xgawk) is used for loading awk library files. This differs from -f in that the first non-option argument is treated as a script.
You need to use the bundled inplace.awk
include file to invoke the extension properly like so:
$ cat file
123 abc
456 def
789 hij
$ gawk -i inplace '{print $1}' file
$ cat file
123
456
789
The variable INPLACE_SUFFIX
can be used to specify the extension for a backup file:
$ gawk -i inplace -v INPLACE_SUFFIX=.bak '{print $1}' file
$ cat file
123
456
789
$ cat file.bak
123 abc
456 def
789 hij
I am happy this feature has been added but to me, the implementation isn't very awkish as the power comes from the conciseness of the language and -i inplace
is 8 characters too long i.m.o.
Here is a link to the manual for the official word.
just a little hack that works
echo "$(awk '{awk code}' file)" > file