usage of sed command

[sivamanikandan]

i found a script in whch sed is used like this
sed -e 's#\(.*).log#\mv & \1_bak.log#'|sh
actually what operaion this will do?

 

[DeboraHarry]

i found a script in whch sed is used like this
sed -e 's#\(.*).log#\mv & \1_bak.log#'|sh
actually what operaion this will do?

Someone is being a bit silly, as there is no need for the -e option here.

It is some sort of substitution, as

s/foo/bar

will substitute foo for bar, but I'm surprised in your example there is no / after the first s. The whole thing looks a bit odd to me, but it seems they are probably trying to rename a file from a .log extension to a 1_bak.log. There is a usenet group, something like comp.unix.shell. I sugget you ask there.

Deborah

 

[Irenicus]

if you get a input as "
abc.log
def.log
..........",
then the first pipeline will substitute it for "
mv abc.log abc_bak.log
mv def.log def_bak.log
...........".
shell reads the output from sed, and executes as commands

- - - Updated - - -

s/foo/bar/ s#foo#bar# s!foo!bar! those work too