noclobber: Protecting files from accidental overwriting. This feature is known as noclobber. Once set, you can protect your files from being overwritten with the shell's > and >> symbols.
This particular option is designed to keep you from accidentally destroying your existing files by redirecting input over an already-existing file.
set noclobber #No more overwriting files with >
If you now redirect command output to an existing file foo, the shell will retort with a message:
foo: File exists.
To override this protection feature, you have to use the ! after the >:
head -5 emp.lst >! foo
To find out the different settings:
set -o
To unset the "noclobber" option:
set +o noclobber
This particular option is designed to keep you from accidentally destroying your existing files by redirecting input over an already-existing file.
set noclobber #No more overwriting files with >
If you now redirect command output to an existing file foo, the shell will retort with a message:
foo: File exists.
To override this protection feature, you have to use the ! after the >:
head -5 emp.lst >! foo
To find out the different settings:
set -o
To unset the "noclobber" option:
set +o noclobber
No comments:
Post a Comment