sed bug ?

[Rostislav]

Hello Timo,

I have seen this problem with Musl basic regular expressions myself. Busybox sed uses C library's regex functions (regcomp, regexec, etc), and Musl versions < 1.1.13 do not support \|, \+ and \? in basic regular expressions. See Musl's changelog here http://git.musl-libc.org/cgit/musl/tree/WHATSNEW , in 1.1.13 release notes it says under "new features":

- regex BRE extensions: \|, \+, \?

The same happens with e. g. busybox grep and other tools that rely on C library's regex functions. Therefore I would prefer to use extended regexes instead.

Best regards,
Rostislav
> On Nov 17, 2016, at 11:56 AM, Timo Teras <timo.teras at iki.fi> wrote:
> 
> Hi,
> 
> The following discrepancy happens on 1.25.1 (and git master) with musl
> c-library:
> 
> ~ $ echo /usr/lib/ | sed 's,\(^/\|\)[^/][^/]*,..,g'
> ../../
> 
> ~ $ echo /usr/lib/ | busybox sed 's,\(^/\|\)[^/][^/]*,..,g'
> /../../
> 
> Any thoughts?
> 
> Thanks,
> Timo
>