MPE/iX Intrinsics Reference Manual (32650-90875)

124 Chapter5
Command Definitions (FCONTROL - FLOCK)
FCONTROL
FCONTROL
NM and CM callable.
Performs various control operations on a file or on the device where the file resides,
including:
• Supplying a printer or terminal carriage control directive.
• Verifying I/O.
• Reading the hardware status word for the device where the file resides.
• Setting a terminal's timeout interval.
• Repositioning a file at its beginning.
• Writing an end-of-file marker.
• Skipping forward or backward to a tape mark.
Syntax
I16V I16V *
FCONTROL(
filenum,itemnum,item );
Parameters
filenum 16-bit signed integer by value (required)
Passes the file number of the file for which the control operation is to be
performed.
itemnum 16-bit signed integer by value (required)
Specifies which operation is to be performed (refer to following list).
item type varies (required)
Passes/returns a value associated with a control operation as indicated by
the corresponding
itemnum parameter (refer to following list).
(KSAM) This parameter is ignored, but must be specified to satisfy
internal requirements.
Itemnum/Mnemonic Item Description
0/U16 General device control:
The value specified is passed to the appropriate device driver. A value from
the driver is returned in
item . Not valid for spooled device files.
1/U16 Carriage control (CCTL):
Passes a carriage control directive to the driver of the specified nonspooled
device file, regardless of whether the file is opened CCTL or NOCCTL. For
spooled devices, use FWRITE to pass carriage control directives. (Refer to