/trunk/root/usr/bin/modunreg

[johnbock]

content=$(grep -v "^$2|" /mod/etc/reg/cgi.reg) 
echo "$content" > /mod/etc/reg/cgi.reg

sed can solve these types of things pretty elegantly

sed -i "/^$2|/d" /mod/etc/reg/cgi.reg

 

[McNetic]

That appears even better, but it imposes the problem of / being part of some of the arguments to modunreg. When changing to

sed -i "\@^$2|@d" /mod/etc/reg/cgi.reg

the problem of the @ (or any other character other than /) being allow in unix filenames arises.
So to get it 100% correct, the arguments would have to be escaped before being fed to sed, right? Or do you see another solution?

 

[johnbock]

If you really want to get tricky you could use an ascii control symbol: something under decimal 32...

 

[McNetic]

That would be hardly maintainable. If the busybox sh would do some of the fancy substitutions bash does, we could do something like

sed -i "\@^${2//\//\\\/}|@d" /mod/etc/reg/cgi.reg

.

I don't think we should drop the support for / in arguments we have now, and we should try to avoid implementing other pitfalls. But maybe picking some other character that's unlikely to be used in arguments may be ok?

 

[johnbock]

I'm not sure about that, I find the following not too hard to read

nil=$(echo -ne '\01')
sed -i "\\${nil}^${2}|${nil}d" /mod/etc/reg/cgi.reg

but if you do insist, I would suggest using star or ampersand.

 

[McNetic]

Your proposal looks good. I didn't think of using a variable for the special character. I implemented this in r2093.

 

[johnbock]

looks good, should we put that in a best practices/howto and link it into the style guide?