Asynchronous Serial Communications Programmer's Reference Manual (32022-90052)

198 Chapter8
Intrinsics Reference
FCONTROL(40)
FCONTROL(40)
Parameters
controlcode 40 — Determines current speed setting.
param 16-bit unsigned integer by reference
(required)
Returns the line speed currently associated with an
asynchronous port in characters per second.
Notes A call to FCONTROL with a controlcode value of 40
allows you to determine the line speed at which an
asynchronous port is currently operating. The speed is
specified in characters per second. You can use the
information to return the port to its original speed
setting after you have changed the line speed through
FCONTROL(37) or FCONTROL(11).
Do not confuse the current line speed returned by this
intrinsic with the default line speed specified during
system configuration through NMMGR. Changing the
line speed through the system intrinsics can cause the
current line speed to be different from the configured
line speed. To reset the line speed of the port to the
default value you can use FCONTROL(37) specifying 0
as the value of param. (Note that FCONTROL(37) will
restore the default terminal type as well.)
Closing the device also restores its settings to
configured default values.
If issued against a terminal connected via PAD, DTC
Telnet, Telnet/iX, or VT, this call will return a CCE
condition code. The value returned in param will be
120 (for 1200 baud) but this value has no meaning for
DTC Telnet, or PAD connections. For Telnet/iX or VT
connections, the value returned in param will typically
be 960 (for 9600 baud) but this value has no meaning.
Condition Codes
CCE Request granted.
CCG Not returned by this intrinsic.
CCL Failed because the file number specified did not belong
to this process or the device is not a terminal.