manticoresearch/api/libsphinxclient/README

Pure C searchd client API library
Sphinx search engine, http://sphinxsearch.com/

API notes
----------

1. API can either copy the contents of passed pointer arguments,
or rely on the application that the pointer will not become invalid.
This is controlled on per-client basis; see 'copy_args' argument
to the sphinx_create() call.

When 'copy_args' is true, API will create and manage a copy of every
string and array passed to it. This causes additional malloc() pressure,
but makes calling code easier to write.

When 'copy_args' is false, API expects that pointers passed to
sphinx_set_xxx() calls will still be valid at the time when sphinx_query()
or sphinx_add_query() are called.

Rule of thumb: when 'copy_args' is false, do not free query arguments
until you have the search result. Example code for that case:

VALID CODE:

	char * my_filter_name;

	my_filter_name = malloc ( 256 );
	strncpy ( my_filter_name, "test", 256 );

	sphinx_add_filter_range ( client, my_filter_name, 10, 20, false );
	result = sphinx_query ( client );

	free ( my_filter_name );
	my_filter_name = NULL;

INVALID CODE:

	void setup_my_filter ( sphinx_client * client )
	{
		char buffer[256];
		strncpy ( buffer, "test", sizeof(buffer) );

		// INVALID! by the time when sphinx_query() is called,
		// buffer will be out of scope
		sphinx_add_filter_range ( client, buffer, 10, 20, false );
	}

	setup_my_filter ( client );
	result = sphinx_query ( client );

--eof--