CreateSemaphore Function

Action

Creates a named or unnamed semaphore object.

Include file

Kernel.bdh

Syntax

CreateSemaphore(in nSecurity : number,
in nInitCount : number,
in nMaxCount : number,
in sName : string): number;

Return value

handle to the semaphore object

Parameter	Description
nSecurity	Security attributes for the semaphore object. This parameter must always be set to NULL.
nInitCount	Initial count for the semaphore object. This value must be greater than or equal to zero and less than or equal to nMaxCount. The initial count value is not set if the specified semaphore object already exists.
nMaxCount	Maximum count for the semaphore object. This value must be greater than zero. The maximum count value is not set if the specified semaphore object already exists.
sName	Name of the semaphore object.

Example

dcltrans
transaction TMain
constMAX_USERS := 25;
var
hSemaphore: number;
begin
hSemaphore := CreateSemaphore(NULL, MAX_USERS,
MAX_USERS, "semaphore");
...
WaitForSingleObject(hSemaphore, INFINITE);
// perform critical work
...
ReleaseSemaphore(hSemaphore, 1);
...
end TMain;