DosUnlockSeg

Bindings:  C, MASM 

This call unlocks a discardable segment. 

 DosUnlockSeg    (Selector) 
 

 Selector (SEL) - input 
    Segment selector to be unlocked. 

 rc (USHORT) - return 
    Return code descriptions are: 

    0         NO_ERROR 
    5         ERROR_ACCESS_DENIED 
    158       ERROR_NOT_LOCKED 
 
 Remarks 

 DosUnlockSeg is called to free memory for possible discard by the system 
 in a low memory situation. The memory being freed is originally allocated 
 by a call to DosAllocSeg or DosAllocHuge with AllocFlags bit 2 set. This 
 memory may have been reallocated by a call to DosReallocSeg or 
 DosReallocHuge after discard by the system. 

 Allocation and reallocation calls for discardable memory automatically 
 lock the memory for access by the calling process. Thus, to access the 
 segment, the caller does not have to lock the segment with DosLockSeg. 
  Once a discardable segment is unlocked by a  DosUnlockSeg request, 
 access to the segment is gained by a successful DosLockSeg request. 

 DosUnlockSeg may also be used on segments that are non-discardable, in 
 which case it has no effect.