bug in grep with CONFIG_EXTRA_COMPAT?

[Natanael Copa]

Hi,

After upgrade to busybox 1.12 shorewall failed to start. A user tracked
it down to this line: grep '^[[:space:]]*$'


I found out that busybox with CONFIG_EXTRA_COMPAT enabled did this:

echo "   " | busybox grep '^[[:space:]]*$' ; echo $? 
1

while gnu grep does:

echo "   " | grep '^[[:space:]]*$' ; echo $? 

0

Turning CONFIG_EXTR_COMPAT off makes busybox behave as gnu grep. Was
this intentional or is it a bug? maybe its a bug in uclibc-0.9.28.3?

thanks!

-nc