Distribution of software

log · 05-12-2003, 10:27 AM

Im a newbie, so I could be totally wrong.

Say if I compile a program with the latest kernel, does that mean that I can just give that executable file to anone with linux, and as long as they have the latest kernel, it will work regardless of distribution?

If that is the case, then why isnt distribution of software easier? download a compressed file, extract it where you want and run it. Rather than compiling (and often not having everything you need to compile) and going through all the hassle? Sure, RPMs are a lot easier (Yes, i use red hat) but not everyone provides them and if any library is required, you HAVE to install the RPM for that library, and not compile from source.

For example, take suns java, no compiling is required and it just works. BTW, yes, I am a java developer

hehe

acid_kewpie · 05-12-2003, 10:35 AM

nope, a bit wrong i'm afraid. when you compile software it will be expecting certain versions of libraries (not the kernel) to be in certain places. often it will work but you could eaily get unresolved symbol errors or other nasy things. for example...

Code:

trevor chris # ldd /bin/ls
        librt.so.1 => /lib/librt.so.1 (0x40020000)
        libc.so.6 => /lib/libc.so.6 (0x40033000)
        libpthread.so.0 => /lib/libpthread.so.0 (0x40161000)
        /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)

this shows what libraries the ls program will be expecting, and it'll fail if those aren't met.

moses · 05-12-2003, 10:53 AM

Most programs require external libraries to compile correctly. You can compile the program "statically", which means you compile the required library routines into the program instead of having it pick up those routines at runtime. However, this makes the compiled binary larger, and since many programs require the same libraries, you would end up duplicating the same routines many many times, which means you would waste an inordinate amount of space.