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This is part of Family API which allow to create dual-os version of program runs under OS/2 and DOS
Note: This is legacy API call. It is recommended to use 32-bit equivalent
This call accesses a shared memory segment previously allocated by another process.
Syntax
DosGetShrSeg (Name, Selector)
Parameters
;Name (PSZ) - input : Address of the name string associated with the shared memory segment to be accessed. The name is an ASCIIZ string in the format of an OS/2 filename in a subdirectory called \SHAREMEM\, for example, \SHAREMEM\PUBLIC.DAT. ;Selector (PSEL) - output : Address of the selector for the shared memory segment.
Return Code
;rc (USHORT) - return:Return code descriptions are: *0 NO_ERROR *2 ERROR_FILE_NOT_FOUND *4 ERROR_TOO_MANY_OPEN_FILES *123 ERROR_INVALID_NAME
Remarks
DosGetShrSeg provides access to a named shared segment allocated by another process with DosAllocShrSeg. The selector returned by DosGetShrSeg is the same as the one returned by the DosAllocShrSeg call.
A usage count is maintained for a named shared segment. Issuing DosGetShrSeg increments the count, and issuing DosFreeSeg decrements the count. When the usage count equals zero, the named shared segment is deallocated. Once the segment has been deallocated, it must be reinitialized by a call to DosAllocShrSeg.
To access shared memory that is allocated by another process with DosAllocSeg and DosAllocHuge requests, a process issues DosGetSeg.
Bindings
C
<PRE> #define INCL_DOSMEMMGR
USHORT rc = DosGetShrSeg(Name, Selector);
PSZ Name; /* Name string */ PSEL Selector; /* Selector of shared segment */
USHORT rc; /* return code /* </PRE>
MASM
<PRE> EXTRN DosGetShrSeg:FAR INCL_DOSMEMMGR EQU 1
PUSH@ ASCIIZ Name ;Name string PUSH@ WORD Selector ;Selector of shared segment (returned) CALL DosGetShrSeg
Returns WORD </PRE>