CMAKE ZM_PERL_SUBPREFIX Slash Issue

[cspenceiv]

Applicable version: 1.28.0
Build environment: Arch Linux x86_64 ABS

The current INSTALL file states:
"ZM_PERL_SUBPREFIX Use a different directory for the zm perl modules. NOTE: This is a subprefix, e.g. lib will be turned into /lib, default: /perl5"

This explanation is either ambiguous/wrong or the scripts are broken behind the scenes. Consider the following examples generated on an Arch ABS x86_64 setup. Keep in mind that pkg/zoneminder is essentially a build directory.

ZM_PERL_SUBPREFIX=lib/perl5
Places the files that should be at pkg/zoneminder/usr/lib/perl5/ into pkg/zoneminder/usr/tmp/zoneminder/src/ZoneMinder-1.28.0/lib/perl5/. This is way off.

ZM_PERL_SUBPREFIX=/usr/lib/perl5/
Places the files at pkg/zoneminder/usr/usr/lib/perl5/.

ZM_PERL_SUBPREFIX=/lib/perl5
Places the files at pkg/zoneminder/usr/lib/perl5/ as originally desired.

Without code changes, you would want to amend the INSTALL file to say:
"ZM_PERL_SUBPREFIX Use a different directory for the zm perl modules. NOTE: This is a subprefix, e.g. /lib will be turned into <prefix>/lib, default: <prefix>/lib/perl5"

Otherwise, it appears that there is an interesting directory slash bug somewhere.

[knight-of-ni]

Zoneminder will install the perl modules into the following folder:
${DESTDIR}${PREFIX}${PERL_SUBPREFIX}

That is why your third attempt works and the others don't.
I've never tried using a relative folder, and I don't see how that could ever work. I'll update the documentation.

[knight-of-ni]

Fixed in commit d8df44f

Note that your original quote isn't quite right. I think github may have stripped out some of it when you pasted it.
ZM_PERL_SUBPREFIX Use a different directory for the zm perl modules. NOTE: This is a subprefix, e.g. lib will be turned into <prefix>/lib, default: <libarch>/perl5

This is essentially correct. I added a "/" for clarification:
ZM_PERL_SUBPREFIX Use a different directory for the zm perl modules. NOTE: This is a subprefix, e.g. /lib will be turned into <prefix>/lib, default: <libarch>/perl5

[cspenceiv]

I just fixed my original post. You were right. I forgot that GitHub recognizes the < and > symbols as HTML.

That fix should make it a little less confusing and save people like me a compile or two.

In respect to using a relative folder, it depends if the prefix was using a trailing slash. But most projects assume that the user does not include a trailing slash so any additional variable content is added to the end of the prefix with a leading slash. Since double forward slashes are acceptable, it always works to assume you need a leading slash.

One solution to absolutely make sure it works: ${DESTDIR}${PREFIX}/${PERL_SUBPREFIX}

But if the documentation is clear, it shouldn't be needed and this is such a minor thing anyway.

[knight-of-ni]

Closing this one out as commit 0cf82a0 rewrites the code in question.