Re: sed file processing?

On 14Feb2014 17:16, Jude DaShiell <[email protected]> wrote:
> That's very useful having restrictions on input files being overwritten, 
> that way we get to see if we like the results before doing anything 
> permanent.

I'm not sure if it was mentioned, but the "-i" flag has two modes.

The plain "-i" mentioned lets you overwrite in place. But adding a
suffix, eg "-i.bak" or even "-i.bak-`date +%Y%m%d`" takes a backup
of the original version as well.

On a personal basis I have a script called "bsed":
  https://bitbucket.org/cameron_simpson/css/src/tip/bin/bsed
that does essentially what GNU sed's -i option does (though it
rewrites the file instead of making a copy and swapping it in, for
reasons I can belabour if anyone really cares), partly to work with
non-GNU seds which don't have -i, and partly because it will
optionally report a diff and also check the sed output status; a
failure such as from a syntacticly invalid sed script won't destroy
the input/output file.

Cheers,
-- 
Cameron Simpson <[email protected]>

Don't have awk? Use this simple sh emulation:
    #!/bin/sh
    echo 'Awk bailing out!' >&2
    exit 2
- Tom Horsley <[email protected]>