This function returns the CODEC procedure name.

#define INCL_MMIOOS2
#define INCL_MMIO_CODEC
#include <os2.h>

PCODECINIFILEINFO    pCODECIniFileinfo;  /*  Pointer. */
PSZ                  pszCODECName;       /*  Pointer. */
PULONG               pulBytesRead;       /*  Byte size read. */
ULONG                rc;                 /*  Return codes. */

rc = mmioQueryCODECName(pCODECIniFileinfo,
       pszCODECName, pulBytesRead);