NAME

       sponge - soak up standard input and write to a file

SYNOPSIS

       sed '...' file | grep '...' | sponge [-a] file

DESCRIPTION

       sponge reads standard input and writes it out to the specified file. Unlike a shell
       redirect, sponge soaks up all its input before writing the output file. This allows
       constructing pipelines that read from and write to the same file.

       sponge preserves the permissions of the output file if it already exists.

       When possible, sponge creates or updates the output file atomically by renaming a temp
       file into place. (This cannot be done if TMPDIR is not in the same filesystem.)

       If the output file is a special file or symlink, the data will be written to it,
       non-atomically.

       If no file is specified, sponge outputs to stdout.

OPTIONS

       -a
           Replace the file with a new file that contains the file's original content, with the
           standard input appended to it. This is done atomically when possible.

AUTHOR

       Colin Watson and Tollef Fog Heen