Stack has a built-in list of associations between dis directories and their associated source directories (e.g. it can automatically map from /dis/ls.dis to /appl/cmd/ls.sbl). Giving the -p option adds a new association to the head of this list: if a module path prefix matches dispath, stack will search for a symbol file in sblpath. If the environment variable $sblpath is set, pairs of items from it are added to the association list, as given as -p options. The -p options take precedence over $sblpath.
$ stack 1 unknown fn() Module $Sys PC 742103 waitfor() shnew.b:105.7, 38 runpipeline() shnew.b:483.2, 14 runit() shnew.b:552.3, 29 init() shnew.b:83.3, 28
The process is executing in the Sys module, a call to sys->read that originated at line 105 (characters 7 to 38) of the waitfor function in shnew.b.
Once again, with the -v option to reveal more:
$ stack -v 1 unknown fn() Module $Sys PC 742103 waitfor(pid=18) shnew.b:105.7, 38 status= "" buf= @b419a4 n=-1 who=-1 runpipeline(ctx=nil, pipeline=@b41454) shnew.b:483.2, 14 pid=18 runit(ctx=nil, pipes=nil) shnew.b:552.3, 29 pipeline=@b41454 init(ctxt=nil, argv=nil) shnew.b:83.3, 28 buf= @b40f04 n=4 arg=@b41634 prompt= "$ " $
|STACK(1 )||Rev: Thu Feb 15 14:42:47 GMT 2007|