DosQueryResourceSize

Syntax

DosQueryResourceSize (hmod, idt)

Parameters

hmod (HMODULE) - input

The handle of the module that has the required resource.

A value of zero means to get the size from the current process. A value other than zero is a module handle that was returned by DosLoadModule.

idt (ULONG) - input

The type identifier of the resource.

Possible values are between 1 and 0xFFFE inclusive. Values from 1 to 255 are reserved for predefinition. Values from 256 and on can be type defined for the resource. The fist 21 values are predefined as follows:

1. RT_POINTER Mouse pointer shape
2. RT_BITMAP Bit map
3. RT_MENU Menu template
4. RT_DIALOG Dialog template
5. RT_STRING String tables
6. RT_FONTDIR Font directory
7. RT_FONT Font
8. RT_ACCELTABLE Accelerator tables
9. RT_RCDATA Binary data
10. RT_MESSAGE Error message tables
11. RT_DLGINCLUDE Dialog include file name
12. RT_VKEYTBL Key to vkey tables
13. RT_KEYTBL Key to UGL tables
14. RT_CHARTBL Glyph to character tables
15. RT_DISPLAYINFO Screen display information
16. RT_FKASHORT Function key area short form
17. RT_FKALONG Function key area long form
18. RT_HELPTABLE Help table for Help manager
19. RT_HELPSUBTABLE Help subtable for Help manager
20. RT_FDDIR DBCS unique/font driver directory
21. RT_FD DBCS unique/font driver

idn (ULONG) - input

The name identifier of the resource.

Possible values are between 1 and 0xFFFE inclusive.

pulsize (PULONG) - output

A pointer to a ULONG in which the size, in bytes, of the resource is returned.

Return Code

ulrc (APIRET) - returns

DosQueryResourceSize returns one of the following values:

• 0 NO_ERROR
• 6 ERROR_INVALID_HANDLE
• 87 ERROR_INVALID_PARAMETER

Remarks

DosQueryResourceSize returns the size of the specified resource object.

Resource objects are read-only data objects that can be accessed dynamically at run time. The access key is two numbers. The first number is a type ID; the second, a name ID. These are similar to the file-extension and file-name portions of a file name.

Resource objects are placed into an executable file by the Resource Compiler (RC.EXE).

This function obtains the size of resources loaded from 16-bit executable files or dynamic link libraries (DLLs), since the size is not explicitly stored in most resources.

Example Code

This example loads the dynamic link module "DISPLAY.DLL," and queries the size of the font directory id=1 resource.

#define INCL_DOSRESOURCES     /* Resource types */
#define INCL_DOSMODULEMGR     /* Module Manager values */
#define INCL_DOSERRORS        /* DOS error values */
#include <os2.h>
#include <stdio.h>

int main(VOID) {
UCHAR     LoadError[256] = "";            /* Area for Load failure information */
PSZ       ModuleName = "C:\\OS2\\DLL\\PMWP.DLL";  /* DLL with resources */
HMODULE   ModHandle  = NULLHANDLE;        /* Handle for module */
ULONG     Size       = 0;                 /* Resource size */
APIRET    rc         = NO_ERROR;          /* API return code */

 rc = DosLoadModule(LoadError,               /* Failure information buffer */
                    sizeof(LoadError),       /* Size of buffer             */
                    ModuleName,              /* Module to load             */
                    &ModHandle);             /* Module handle returned     */
 if (rc != NO_ERROR) {
    printf("DosLoadModule error: return code = %u\n", rc);
    return 1;
 }

 rc = DosQueryResourceSize(ModHandle,     /* Handle for DLL containing resources */
                           RT_POINTER,    /* Ask for  Pointer                    */
                           1L,            /*          with an ID of 1            */
                           &Size);        /* The resource size is returned.      */

 if (rc != NO_ERROR) {
    printf("DosGetResource error: return code = %u\n", rc);
    return 1;
 } else {
    printf("Resource is %u bytes in size.\n", Size);
 } /* endif */

return NO_ERROR;
}

Related Functions

• DosFreeResource
• DosGetResource
• DosLoadModule