Specifications

4 USE OF SPY.APP
4-3
Other data
The "Process ID" of a process is essentially the address of the control block of the application in the
Operating System data space, although the top nibble reflects how many times that same slot has been re-
used since the last reset (the top nibble will therefore always be zero for sys$mang, sys$fsrv, and
sys$wsrv). When processes talk to each other, for example in conjunction with the
Bring
menu option,
they need to know each other's PID ("Process ID").
The IO Semaphore count basically keeps track of how many outstanding events a process has to respond
to. This will usually be -1 or zero, but if you task to the System Screen and then straight back to
Spy
again, you may see the count for sys$shll momentarily go as high as three.
Logging Window Server statistics
The menu command
Log client
produces information in text file form as to the structure of the windows,
GCs, fonts, bitmaps, and other Window Server objects "owned" by an application. This information may
of use in determining why certain drawing fails to appear on the screen. For example, it may be that a
window is positioned wrongly, that the window is obscured by another, or that the current GC is set up
incorrectly - any such failure can be seen from the log file.
The menu command
Log all clients
repeats this process for
all
the clients of the Window Server.
The
Log client
command can, in effect, be invoked even when
Spy
is in background. Just press the key
combination
SHIFT
+
CONTROL
+
PSION
+
N
and a dump of the Window Server object usage of the foreground
application will be created - by default in the file
\opl\wsreport.lis
. (This feature works because
Spy
has
"captured" this key combination.)