NAME

libwindows − windowing terminal function library

SYNOPSIS

cc [flag ...] file ... −lwindows [library ...]

int openagent (void);
int New (int cntlfd, int origin_x, int origin_y,
  int corner_x, int corner_y);
int Newlayer (int cntlfd, int origin_x, int origin_y,
  int corner_x, int corner_y);
int openchan (int chan);
int Runlayer (int chan, char ∗command);
int Current (int cntlfd, int chan);
int Delete (int cntlfd, int chan);
int Top (int cntlfd, int chan);
int Bottom (int cntlfd, int chan);
int Move (int cntlfd, int chan, int origin_x, int origin_y);
int Reshape (int cntlfd, int chan, int origin_x, int origin_y,
  int corner_x, int corner_y);
int Exit (int cntlfd);

DESCRIPTION

This library of routines enables a program running on a host UNIX system to perform windowing terminal functions [see layers(1)]. 

The openagent routine opens the control channel of the xt(7) channel group to which the calling process belongs.  Upon successful completion, openagent returns a file descriptor that can be passed to any of the other libwindows routines except openchan and Runlayer.  (The file descriptor can also be passed to the close system call.)  Otherwise, the value −1 is returned. 

The New routine creates a new layer with a separate shell.  The origin_x, origin_y, corner_x, and corner_y arguments are the coordinates of the layer rectangle.  If all the coordinate arguments are 0, the user must define the layer’s rectangle interactively.  The layer appears on top of any overlapping layers.  The layer is not made current (that is, the keyboard is not attached to the new layer).  Upon successful completion, New returns the xt(7) channel number associated with the layer.  Otherwise, the value −1 is returned. 

The Newlayer routine creates a new layer without executing a separate shell.  Otherwise it is identical to New, described above. 

The openchan routine opens the channel argument chan which is obtained from the New or Newlayer routine.  Upon successful completion, openchan returns a file descriptor that can be used as input to write(2) or close(2).  Otherwise, the value −1 is returned. 

The Runlayer routine runs the specified command in the layer associated with the channel argument chan.  This layer is usually a layer previously created with Newlayer.  Any processes currently attached to this layer will be killed, and the new process will have the environment of the layers process. 

The Current routine makes the layer associated with the channel argument chan current (that is, attached to the keyboard). 

The Delete routine deletes the layer associated with the channel argument chan and kills all host processes associated with the layer. 

The Top routine makes the layer associated with the channel argument chan appear on top of all overlapping layers. 

The Bottom routine puts the layer associated with the channel argument chan under all overlapping layers. 

The Move routine moves the layer associated with the channel argument chan from its current screen location to a new screen location at the origin point (origin_x, origin_y).  The size and contents of the layer are maintained. 

The Reshape routine reshapes the layer associated with the channel argument chan.  The arguments origin_x, origin_y, corner_x, and corner_y are the new coordinates of the layer rectangle.  If all the coordinate arguments are 0, the user is allowed to define the layer’s rectangle interactively. 

The Exit routine causes the layers program to exit, killing all processes associated with it. 

FILES

ULIBDIR/libwindows.a   windowing terminal function library
ULIBDIR   usually /usr/lib

SEE ALSO

layers(1), close(2), write(2), jagent(5). 

DIAGNOSTICS

Upon successful completion, Runlayer, Current, Delete, Top, Bottom, Move, Reshape, and Exit return 0, while openagent, New, Newlayer, and openchan return values as described above under each routine.  If an error occurs, −1 is returned. 

NOTES

The values of layer rectangle coordinates are dependent on the type of terminal.  This dependency affects the routines that pass layer rectangle coordinates: Move, New, Newlayer, and Reshape.  Some terminals will expect these numbers to be passed as character positions (bytes); others will expect the information to be in pixels (bits). 

For example, for a terminal with New, Newlayer, and Reshape minimum values of 8 (pixels) for origin_x and origin_y and maximum values of 792 (pixels) for corner_x and 1016 (pixels) for corner_y, the minimum layer size is 28 by 28 pixels and the maximum layer size is 784 by 1008 pixels.

It is recommended that applications use /dev/xt/??[0-7] instead of /dev/xt??[0-7] when accessing the xt driver. 

  —  Layers Windowing Utilities