OpenLDAP Faq-O-Matic : OpenLDAP Software FAQ : Installation :
FD_SETSIZE is too small, how do I raise it?|
|In current versions of OpenLDAP Software, one can define OPENLDAP_FD_SETSIZE to raise FD_SETSIZE. That is,
env CPPFLAGS="-DOPENLDAP_FD_SETSIZE=8192" ./configure
will cause FD_SETSIZE to be set to 8192.
|When using older releases of OpenLDAP Software, depending on the system, one might be able to:
env CPPFLAGS="-DFD_SETSIZE=8192" ./configure ...
to raise the FD_SETSIZE. If this results in compilation errors, you'll either have to hack system headers or back port the <ac/fdset.h> solution to the older release.
|Note: redefining FD_SETSIZE on some platforms, especially very old platforms, may require rebuilding of libc and possibly kernel changes. However, on many modern platforms resizing FD_SETSIZE can safely be done without rebuilding the world.
|What versions are "current versions of OpenLDAP Software" and what exactly are "older releases of OpenLDAP Software" ? I use 2.2.30 and it seems to understand OPENLDAP_FD_SETSIZE, but I do not think it's a "current" version.
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