Question

I need to interface libnetcdf with PHP. (the php-netcdf on google code is broken)

Here’s netcdf.i :

%module netcdf
 %{
 /* Includes the header in the wrapper code */
 #include "netcdf.h"
 %}

 /* Parse the header file to generate wrappers */
 %include "netcdf.h"

I did :

gcc `php-config --includes` -fpic -c netcdf_wrap.c
gcc -shared netcdf_wrap.o -o netcdf.so

but when loading the extension in php, I get :

Unable to load dynamic library netcdf.so:
undefined symbol: ncerr in Unknown on line 0

It’s the first time I try something like that. Am I missing something ?

ADDED -lnetcdf flag.

now, I got : undefined symbol: zend_error_noreturn. fixed replacing zend_error_noreturn by zend_error in netcdf_wrap.c

Answer 1

Your immediate problem is caused by not linking against libnetcdf. You need the -l flag for gcc to do so:

gcc -shared netcdf_wrap.o -o netcdf.so -lnetcdf
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