im_package *im_load_plugin( char *name )
This function opens the named file, searches it for a symbol named
package_table
, and adds any functions it finds to the VIPS function
database. When you search for a function, any plug-ins are searched first,
so you can override standard VIPS function with your own code.
The function returns a pointer to the package it added, or NULL
on error.
int im_close_plugins( void )
This function closes all plug-ins, removing then from the VIPS function database. It returns non-zero on error.