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From: maf@thor.dbsm.oz.au (Martin Foord)
Newsgroups: comp.unix.shell
Subject: Re: sed man page error (Was "Re: sed question")
Message-ID: <1991May29.074028.13085@dbsm.oz.au>
Date: 29 May 91 07:40:28 GMT
Article-I.D.: dbsm.1991May29.074028.13085
References: <3880@wb3ffv.ampr.org> <1991May16.085837.1368@ultra.com> <1991May17.211650.2025@ultra.com>
Sender: maf@dbsm.oz.au (Martin Foord)
Reply-To: maf@thor.dbsm.oz.au (Martin Foord)
Distribution: comp
Organization: SBC Dominguez Barry Ltd
Lines: 65

In article <1991May17.211650.2025@ultra.com> marc@mercutio.ultra.com (Marc Kwiatkowski {Host Software-AIX}) writes:
>I'd point out the sed documentation error that exists in every
>sed man page I've ever seen.
>
>From 4.3BSD URM sed man page:
>
>	n Copy the pattern space to the standard output.  Replace
>	  the pattern space with the next line of input.
>
>It should read:
>
>	n Copy the pattern space to the standard output unless
>	  "-n" flag has been specified.  Replace
>	  the pattern space with the next line of input.
>
>It is surprising that this documentation error has existed for
>so long, and has been reproduced so faithfully by numerous
>Unices.  It makes one suspect that the additional features
>of sed aren't used by many.  

Yes. I think so. Here are a few more bugs in the man page I've discovered :

:
:                 p           Print  the  pattern   space   if   a
:                             replacement was made.

Shouldn't this be something like :

	Print the pattern space if a replacement was made and the '-n' option
has been specifyed.

:
:                 w wfilename Write: append the pattern  space  to
:                             wfilename if a replacement was made.
:
...
:
:     (2)w wfilename
:                 Write: append the pattern space to wfilename.
:

And a nasty but subtle one in both of the above writes, should probably read
something like :

	Write :	Create a new file wfilename and then append the pattern space
to wfilename.

An unsuspecting reader of the manual could assume that w will NOT clobber
wfilename first but append on the already existing wfilename.
 
>If you'll allow me to get on my soapbox, I'd like to campaign
>for sed.  sed's syntax is somewhat obtuse, but it takes far
>less time to load than awk.  Since most of shell-script

Yes, I tend to agree here. The major problem with sed is as you say, the
arcane syntax, and lots of backslash regexs. Therefore it's not a trivial
exercise to learn the FULL capabilities of sed and so few do. It'd be good
to see this updated (eg: give sed a more egrepish like set of regexs), then
again one could basically be doing all this with perl -[p|n]e ...

Martin.
-- 
Martin Foord.				MHSnet/ACSnet:  maf@dbsm.oz.au
SBC Dominguez Barry.			Internet Gateway:
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