diff options
Diffstat (limited to 'man/2/devpointer')
| -rw-r--r-- | man/2/devpointer | 33 |
1 files changed, 27 insertions, 6 deletions
diff --git a/man/2/devpointer b/man/2/devpointer index 6433221c..19c82f13 100644 --- a/man/2/devpointer +++ b/man/2/devpointer @@ -5,9 +5,11 @@ devpointer \- I/O interface for the pointer device .EX include "draw.m"; # for Draw->Pointer include "devpointer.m"; -ptr:= load Devpointer Devpointer->PATH; +ptr := load Devpointer Devpointer->PATH; -init: fn(file: string, posn: chan of ref Draw->Pointer): int; +init: fn(); +reader: fn(file: string, posn: chan of ref Draw->Pointer, + pid: chan of (int, string)); bytes2ptr: fn(buf: array of byte) : ref Draw->Pointer; ptr2bytes: fn(ptr: ref Draw->Pointer): array of byte; .EE @@ -20,11 +22,30 @@ converting them to adts. .PP .B Init -spawns a process to read continually the pointer device specified by -.I file -and send a +must be called before any other operation of the module. +.PP +.B Reader +should be spawned by the caller. +It opens the pointer device specified by +.IR file , +and sends a value +.BI ( id,\ err ) +on channel +.IR pid . +On success, +.I id +is the process ID of the spawned process and +.I err +is nil; on an error, +.I err +is a diagnostic, and +.I id +is undefined. +If the file was opened successfully, +.B reader +continually reads the pointer device and sends .B Pointer -adts over the channel specified by +adts over the channel .IR posn . If .I file |