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diff --git a/doc/C-API.txt b/doc/C-API.txt deleted file mode 100644 index edf0d56..0000000 --- a/doc/C-API.txt +++ /dev/null @@ -1,198 +0,0 @@ -============================================================================== - Description of C API bindings -============================================================================== - -This file contains information specific to the C bindings. Refer to the generic -API documentation for information that is not specific to C bindings. See also -C-HOWTO.txt . - - - - -Data types -========== - - -C allows only a limited set of data types. Types from the abstract API that -are not available in C are used as follows: - -bool - int with values 1 for true and 0 for false - -string - char* NUL-terminated string; calls that return char* allocate it dynamically -and the caller must deallocate it by calling free() - -arrays ( int[], string[] ) - intarr, stringarr (see below) - -windowinfo - DapiWindowInfo (see below) - - -DapiConnection --------------- - -Opaque data type that contains all internal data. Most calls require it -as the first argument. - - -DapiWindowInfo --------------- - -Some call require information about a window related to the call. This structure -holds data about such window. Call dapi_windowInfoInitWindow() to fill in the info -or use the convenience _Window functions. - - -void dapi_windowInfoInitWindow( DapiWindowInfo* winfo, long window ) --------------------------------------------------------------------- - -Initializes DapiWindowInfo with data about given window. - -winfo: DapiWindowInfo data structure to initialize -window: Window handle (as used with X Window System) - - -void dapi_freeWindowInfo( DapiWindowInfo winfo ) ------------------------------------------------- - -Frees DapiWindowInfo structure data. - -winfo: DapiWindowInfo data structure to free data from. - - -intarr ------- - -A structure representing an integer array. -typedef struct - { - int count; - int* data; - } intarr; -'count' is number of elements, 'data' is array of elements. - - -void dapi_freeintarr( intarr arr ) ----------------------------------- - -Convenience function that frees dynamically allocated data from intarr. -All DAPI functions that return intarr allocate the data dynamically -and the caller must free it. - - -stringarr ---------- - -A structure representing a string array. -typedef struct - { - int count; - char** data; - } stringarr; -'count' is number of elements, 'data' is array of char* strings. - - -void dapi_freestringarr( stringarr arr ) ----------------------------------------- - -Convenience function that frees dynamically allocated data from stringarr. -All DAPI functions that return stringarr allocate the data dynamically -and the caller must free it. - - - - - - -Utility functions -================= - - -DapiConnection* dapi_connect( void ) ------------------------------------- - -Tries to connect to a running backend daemon. - -Returns: NULL if failed, opaque connection handle if success. - - -DapiConnection* dapi_connectAndInit( void ) -------------------------------------------- - -Convenience function that calls dapi_connect() and if successful -also performs initialization by calling dapi_Init() (see later). - - -void dapi_close( DapiConnection* conn ) ---------------------------------------- - -Closes a connection to a backend daemon. - -conn: Opaque connection handle. - - -int dapi_socket( DapiConnection* conn ) ---------------------------------------- - -Returns a file descriptor that can be used with system functions such as select() -to watch activity. - -conn: Opaque connection handle. -Returns: file descriptor - - -void dapi_processData( DapiConnection* conn ) ---------------------------------------------- - -Processes pending incoming data on the connection socket. - -conn: Opaque connection handle. - - -int dapi_readCommand( DapiConnection* conn, int* comm, int* seq ) ------------------------------------------------------------------ - -Reads a command header of the next incoming command request/reply. - -conn: Opaque connection handle. -comm: Id number of the incomming command. -seq: Sequence number of the incoming command. -Returns: 1 if successful, 0 if failure - - -TBD: -typedef void (*DapiGenericCallback)( DapiConnection* conn, int command, int seq ); -DapiGenericCallback dapi_setGenericCallback( DapiConnection* conn, DapiGenericCallback callback ); -void dapi_genericCallback( DapiConnection* conn, int command, int seq ); - - - - - - -Calls functions -=============== - - -There are several ways to invoke the API calls. For call XYZ there is: - -- lowlevel dapi_writeCommandXYZ(), dapi_readReplyXYZ() calls that write a command - request resp. read a command reply. - - dapi_writeCommandXYZ() writes a command header and all command arguments and - returns either 0 if failure or sequence number of the command. Each command request - has a specific sequence number assigned and is used to identify replies. - - dapi_readCommandXYZ() reads all reply arguments. It doesn't read command header, - dapi_readCommand() must be called first to identify a command. Returns 1 if success - or 0 if failure. - - Include file dapi/comm_generated.h contains all function prototypes. - -- blocking dapi_XYZ() call that writes a command request and waits for a reply. - Include file dapi/calls_generated.h contains all function prototypes. - -- non-blocking dapi_callbackXYZ() call that writes a command and invokes the passed - callback when a reply comes. - - dapi_callbackXYZ() returns a sequence number if success or 0 if failure - - Include file dapi/callbacks_generated.h contains all function prototypes. |