Entry

When starting apache i get "Cannot load /usr/local/apache_1.3.12/libexec/libphp4.so into server: undefined symbol: uncompress"

undefined reference to `compress'

Nov 5th, 2000 11:33
David Greenberg, Thomas tanghus, Guest, Matthew Gregory, Beauford Beauford, http://www.info-zip.org/pub/infozip/zlib/

"uncompress" comes from libz.so.<version>, which is a DSO library that 
must be installed on your system in a library directory.  This library 
provides support for various compression utilities, similar to the 
functionality of the <uncompress> or <gunzip> commands.

If you don't have it already, install the latest version of zlib.  (See 
the link above.)  

Be sure to run <ldconfig> as root to configure your newly installed 
libz.so library file. ldconfig creates a shared library cache and 
maintains symbolic links to the actual library files, with appropriate 
version numbers.  

The above problem may occur regardless of whether you configure PHP's 
build using the --without-zlib option.

Why?

If you compile in MySQL support -- and most people do -- MySQL's client 
library (also a dynamically linked library) requires the functionality 
of ZLIB.

To fix the problem, all you have to do, right before you run 
PHP's "make", is 
to edit your top-level Makefile and modify the following line:

LTLIBRARY_LDFLAGS = -lz [ ... ]

The important part is the -lz, which is not present by default.

Now, you can run make and then make install, and everything should work 
fine.

You can verify dependencies of the libphp4.so module as follows:

[davidg@www apache]$ ldd libexec/libphp4.so
        libz.so.1 => /usr/lib/libz.so.1 (0x40129000)
        libpam.so.0 => /lib/libpam.so.0 (0x40138000)
        libdl.so.2 => /lib/libdl.so.2 (0x40140000)
        libgd.so.1 => /usr/lib/libgd.so.1 (0x40143000)
        libresolv.so.2 => /lib/libresolv.so.2 (0x40179000)
        libm.so.6 => /lib/libm.so.6 (0x40188000)
        libcrypt.so.1 => /lib/libcrypt.so.1 (0x401a5000)
        libnsl.so.1 => /lib/libnsl.so.1 (0x401d2000)
        libc.so.6 => /lib/libc.so.6 (0x401e8000)
        /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x80000000)
[davidg@www apache]$ 

See how libz is listed?  This is *essential*.  If this occurs, you 
should be in good shape.

P.S: I ran into this problem on RH Linux 6.1 with patches. I have not 
tested on other systems.  zlib is available for almost every flavor of 
UNIX.

PPS: If you don't use MySQL and you don't plan to use the compression 
library, configure using --without-zlib.

Cheers!