linux - [Solved-5 Solutions] Awk save modifications in place - ubuntu - red hat - debian - linux server - linux pc

If there is an option to write changes to file, similar to sed where you would use -i option to save modifications to a file.

You could use redirection to write changes. However is there an option in awk to do that?

In latest GNU Awk , 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

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.

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

someprocess < file > file

echo "$(awk '{awk code}' file)" > file

echo "$(awk '{awk code}' file)" > file