XtAppAddInput man page

XtAppAddInput, XtRemoveInput — register and remove an input source

Syntax

XtInputId XtAppAddInput(XtAppContext app_context, int source, XtPointer condition, XtInputCallbackProc proc, XtPointer client_data);

void XtRemoveInput(XtInputId id);

Arguments

app_context
Specifies the application context that identifies the application.
client_data
Specifies the argument that is to be passed to the specified procedure when input is available.
condition
Specifies the mask that indicates a read, write, or exception condition or some operating system dependent condition.
id
Specifies the ID returned from the corresponding XtAppAddInput call.
proc
Specifies the procedure that is to be called when input is available.
source
Specifies the source file descriptor on a UNIX-based system or other operating system dependent device specification.

Description

The XtAppAddInput function registers with the Intrinsics read routine a new source of events, which is usually file input but can also be file output. Note that file should be loosely interpreted to mean any sink or source of data. XtAppAddInput also specifies the conditions under which the source can generate events. When input is pending on this source, the callback procedure is called.

The legal values for the condition argument are operating-system dependent. On a UNIX-based system, the condition is some union of XtInputReadMask, XtInputWriteMask, and XtInputExceptMask. The XtRemoveInput function causes the Intrinsics read routine to stop watching for input from the input source.

See Also

XtAppAddTimeOut(3),XtAppAddSignal(3)
X Toolkit Intrinsics - C Language Interface
Xlib - C Language X Interface

Bugs

In ANSI C it is necessary to cast the condition to an XtPointer, e.g.:

XtAppAddInput(app_context,

source,
(XtPointer) (XtInputReadMask | XtInputWriteMask),
proc,
client_data);

Referenced By

XtAddInput(3), XtAppAddSignal(3), XtAppAddTimeOut(3).

XtRemoveInput(3) is an alias of XtAppAddInput(3).

libXt 1.1.5 X Version 11 XT FUNCTIONS