Back to Slack...

[vwgtiturbo]

Well, I finally got fed up with RH9 again, thanks in part to RPM (for the third time in a year) and am installing Slack 9.1. I was wondering... as far as compiling programs from source... this is what makes the programs run faster, correct? Since they are optimized for your system? Now, when you 'make' and all that stuff, does the system automatically perform this optimizing as it compiles, or does it just do an i386 type install, and if you want the optimizations, you have to compile it a certain way? Also, let's say I have the source from program A in a directory. After the compilation, can I just delete the source directory, or does it just depend on the program?

[gaxprels]

It depends on what flags are set by the Makefile when you run make. You can override these flags for better optimizations, BUT... it's not recommended. Optimizations CAN break functionality and introduce bugs. If the creator of the code didn't test his code with those optimization flags set, then you can't expect the code to work exactly like you think it should. Your safest bet is to just "./configure && make && make install" rather than trying to set optimizations the code hasn't been tested with.

[SkyNet]

And yes, having it compiled for your system is going to have it running faster. Even without certain optimizations.

[vwgtiturbo]

Well, when you install something via RPM, isn't it just "configure/make/make install" via a script? If that were the case, then wouldn't all of your RPM installs be 'compiled' for your system? And again, if that were the case, why on earth would there be 'i386' RPMs? I am just curious, as now that I am trying to learn the stuff instead of relying on the distro to figure it out for me, it all seems greek...
Also, I noticed, Gaxprels, you use the '&&' in a couple of your posts... I know that '&' runs a command in the background, but the '&&'... does that mean, 'run in the background, and when that is done, run 'command x'..."?

[gaxprels]

RPM's are usually binary (already compiled on another system) and thus have compiler options turned on to make them compatible across several architectures (meaning i386, i486, i586, and i686, not just your processor) so... no, RPM is NOT like "./configure && make && make install"

the "&&" in the line:
./configure && make && make install

means this:
configure. if nothing went wrong with configure, then run make... otherwise quit... if nothing went wrong with make, then run make install...

you could also do:
./configure; make; make install

but... that would run make and then run make install regardless of any errors in the previous command given.

Most people just do:
./configure
make
make install

it's all a matter of preference

[vwgtiturbo]

I see... thanks for the clarification. I needed that

[dox]

i hate rpm!! compiling makes it sooo much easier ;D

[vwgtiturbo]

compiling is easy if you know how, and you know where the stuff goes when it is done, and what where it needs to go! I am clueless. I downloaded a bunch of articles about it, just to give me aheads up.
Question: after configure/make/makeinstall, can you just remove the directory that the source is in? Or do you need it to run the program after it is compiled? I ask this because I am a little anal about keeping my systems organized (programs here, docs there, etc.) and I want to know if I will be able to move the source directory after compiling (or remove) or if I need to put the source where I want it THEN compile.

[vwgtiturbo]

One more question... if you are running configure/make/makeinstall, and there are errors, does it dump alot of garbage files in the directory (that you need to get rid of before trying again)?

[gaxprels]

For most programs, a "./configure && make && make install" will allow you to delete the source directory when you are done. I can't think of any programs where you need it after it is installed, but that doesn't mean there aren't any. The best thing to do would be to delete it, and if it breaks, just unpack the tarball, and "./configure && make" then don't worry about the "make install" since it's already installed.