DosGetResource (OS/2 1.x)

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This call returns the segment selector of the specified resource segment.


DosGetResource (ModHandle, TypeID, NameID, Selector)


ModHandle (HMODULE) - input
The location of the resource segment.
0 - The executable file of the current process.
<> 0 - A handle to a dynamic link module returned by DosLoadModule.
TypeID (USHORT) - input 
A 16 bit resource type ID (see Remarks).
NameID (USHORT) - input 
A 16 bit resource name ID (see Remarks).
Selector (PSEL) - output 
The address of a word where the resource segment selector is returned.

Return Code

rc (USHORT) - return
Return code descriptions are:
  • 0 NO_ERROR


Resource segments are read-only data segments that can be accessed dynamically at run time. The access key consists of two 16-bit numbers, the first of which is a type ID and the second, a name ID. These numbers are similar in concept to the file extension and file name portions of a file name.

The advantage of resource segments is that they can be bundled into an application's executable file, so a single file contains all of the code and data for an application.

It is recommended that resource segments obtained through DosGetResource only be freed using DosFreeSeg.

OS/2 Version 1.2 added two new functions, DosGetResource2 and DosFreeResource, to load and free an application specific resource. DosGetResource2 returns a far pointer to a resource rather than the selector returned via DosGetResource. It is recommended that applications targeted for OS/2 1.2 use DosGetResource2 and DosFreeResource. Applications that wish to execute on OS/2 1.1 and 1.2 should use the OS/2 run-time dynamic link capabilities, DosLoadModule and DosGetProcAddr, to get the address of DosGetResource2 and DosFreeResource when executing on OS/2 1.2. If the DosGetProcAddr call to obtain the address of DosGetResource2 and DosFreeResource fails, the application can call DosGetResource and DosFreeSeg. Applications that use DosGetResource2 and DosFreeResource allow OS/2 to optimize memory allocation associated with the applications resource.




USHORT  rc = DosGetResource(ModHandle, TypeID, NameID, Selector);

HMODULE ModHandle;     /* Module handle to get resource from */
USHORT  TypeID;        /* 16 bit resource type ID */
USHORT  NameID;        /* 16 bit resource name ID */
PSEL    Selector;      /* where to return selector */

USHORT  rc;            /* return code */


EXTRN  DosGetResource:FAR

PUSH   WORD    ModHandle    ;Module handle to get resource from
PUSH   WORD    TypeID       ;16 bit resource type ID
PUSH   WORD    NameID       ;16 bit resource name ID
PUSH@  WORD    Selector     ;Resource selector (returned)
CALL   DosGetResource

Returns WORD