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xtappaddinput(1) [hpux man page]

XtAppAddInput() 														   XtAppAddInput()

Name
  XtAppAddInput - register a procedure to be called when there is activity on a file descriptor.

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

Inputs
  app_context
	    Specifies the application context.

  source    Specifies the file descriptor (on a POSIX-based system) to monitor.

  condition Specifies a mask that indicates a read, write, or exception condition or some operating-system-dependent condition.

  proc	    Specifies the procedure that is to be called when condition occurs on source.

  client_data
	    Specifies data to be passed to proc when it is invoked.

Returns
  A handle of type XtInputId that can be passed to XtRemoveInput() to unregister this input procedure.

Description
  XtAddInput() registers a file descriptor source to be monitored by XtAppNextEvent() and a procedure proc to be called with data client_data
  when the condition (such as "input ready" or "error") condition arises.

  On a POSIX-based system, the supported values for condition are XtInputReadMask, XtInputWriteMask, or XtInputExceptMask.  These values can-
  not be ORed together.  On non-POSIX systems, the types of source and condition will be operating-system dependent.

  See XtInputCallbackProc(2) for an explanation of how to write an input callback.

  See the POSIX select() system call for more information on the possible file descriptor conditions that can be selected for.

Usage
  XtAppAddInput()  allows  an Xt application to receive non-X based events through the same event loop that delivers X events.	File descrip-
  tors in POSIX are a very general mechanism, and XtAppAddInput() can be used to receive notification when the user types a command to stdin,
  when a child process closes a pipe, or when there is data available on an RPC socket, for example.

  An input callback can be unregistered by calling XtRemoveInput() and passing the XtInputId returned by this function.

  Note	that  when  reading from a socket, you should be careful not to close the end of the socket that is waiting before exiting XtAppMain-
  Loop().  If you do this, you will get an infinite loop, in which the callback is called repeatedly, while the Intrinsics wait for an EOF to
  be read.

Structures
  The XtInputId type is defined as follows:

     typedef unsigned long XtInputId;

See Also
  XtRemoveInput(1),
  XtInputCallbackProc(2).

Xt - Event Handling														   XtAppAddInput()

Check Out this Related Man Page

XtAppAddInput(3)						   XT FUNCTIONS 						  XtAppAddInput(3)

NAME
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 XtInpu- tReadMask, 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); X Version 11 libXt 1.1.3 XtAppAddInput(3)
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