The %setflush() function sets the flush periods.
For Windows: Not Supported
oldp = %setflush(newp, newfp)
The normal flush period is set to the number of seconds specified by newp, the forced flush period to newfp and the previous values are returned into oldp. The upper 16 bits of the (int) oldp is the value of the forced flush period, and the lower 16 bits, the value of the normal flush.
If newp is null, no change is made to the normal flush.
If newfp is equal to -2, no change is made to the forced flush.
If newfp is equal to -1, the forced flush is disabled.
If newfp is equal to 0, the forced flush is set into immediate write mode.