[Cialug] sed -e -e

[jim kraai]

$ grep "yak yak" ~/Maildir/* | grep "From:"
From: Todd Walton

can confirm, needs a pipe

yes, that was inaccurate and fun.  I have no shame

:-D


On Wed, May 8, 2019, 12:06 Jeffrey Ollie <jeff at ocjtech.us> wrote:

> On Wed, May 8, 2019 at 11:20 AM Charles Dunbar <ccdunbar at gmail.com> wrote:
>
> > >
> > > As an aside, I sometimes wish I could do that with grep, instead of
> > > using pipes. Like, grep a file for lines that contain "pattern1" *and*
> > > "pattern2": grep -e "pattern1" -e "pattern2" file
> >
> > Good news!
> >
> > `egrep "pattern1|pattern2" file`
> > `grep -E "pattern1|pattern2" file`
> >
>
> Which doesn't do what Todd asked for - "|" is an OR condition, when Todd
> wants lines that contain both. Off the top of my head I can't think of a
> way that grep can do what Todd wants except to pipe the results of one grep
> through another. As powerful as grep and regular expressions are they do
> have limits.
>
> You could use:
>
> (pattern1.*pattern2)|(pattern2.*pattern1)
>
> but that would fail if it's possible for the patterns to overlap.
>
> Sed can do it though:
>
> cat file | sed -e '/pattern1/!d' -e '/pattern2/!d'
>
> That should output only lines from "file" that contain both patterns.
>
>
> > On Wed, May 8, 2019 at 11:04 AM Todd Walton <tdwalton at gmail.com> wrote:
> >
> > > It looks to me like if I run a sed command with multiple "-e" scripts,
> > > each one applies in turn. If I add a line that says "blah blah" with
> > > one "-e", and then a subsequent "-e" replaces "blah" with "yak", I'll
> > > end up with text that says "yak yak". I was wondering if each one
> > > applied in turn, or if each one operated on the original text, or
> > > what. But it seems to be that it's basically adding each "-e" as a
> > > line to a full script.
> > >
> > > As an aside, I sometimes wish I could do that with grep, instead of
> > > using pipes. Like, grep a file for lines that contain "pattern1" *and*
> > > "pattern2": grep -e "pattern1" -e "pattern2" file
> > >
> > > --
> > > Todd
> > > _______________________________________________
> > > Cialug mailing list
> > > Cialug at cialug.org
> > > https://www.cialug.org/cgi-bin/mailman/listinfo/cialug
> > >
> > _______________________________________________
> > Cialug mailing list
> > Cialug at cialug.org
> > https://www.cialug.org/cgi-bin/mailman/listinfo/cialug
> >
>
>
> --
> Jeff Ollie
> The majestik møøse is one of the mäni interesting furry animals in Sweden.
> _______________________________________________
> Cialug mailing list
> Cialug at cialug.org
> https://www.cialug.org/cgi-bin/mailman/listinfo/cialug
>