Cancels all or a selected subset of the Set Timer requests
    previously issued by the current image executing in a process.
    Cancellation is based on the request identification specified
    in the Set Timer ($SETIMR) service. If you give the same request
    identification to more than one timer request, all requests with
    that request identification are canceled.

    Format

      SYS$CANTIM  [reqidt] ,[acmode]

    C Prototype

      int sys$cantim  (unsigned __int64 reqidt, unsigned int acmode);

1  –  Arguments

 reqidt

    OpenVMS usage:user_arg
    type:         quadword
    access:       read only
    mechanism:    by value
    Request identification of the timer requests to be canceled.
    If you specify it as 0 (the default), all timer requests are
    canceled. The reqidt argument is a quadword containing this
    identification.

 acmode

    OpenVMS usage:access_mode
    type:         longword (unsigned)
    access:       read only
    mechanism:    by value
    Access mode of the requests to be canceled. The acmode argument
    is a longword containing the access mode.

    The $PSLDEF macro defines the following symbols for the four
    access modes:

    Symbol         Access Mode

    PSL$C_KERNEL   Kernel
    PSL$C_EXEC     Executive
    PSL$C_SUPER    Supervisor
    PSL$C_USER     User

    The most privileged access mode used is the access mode of the
    caller.