:trace-output
stream
This option allows you to direct trace output to a stream other than the listener in which the original function call was made. By using this you can arrange to dispatch traced output from different functions to different places.
Consider the following example:
CL-USER 129 > (setq str (open "trace.txt" :direction :output))
Warning: Setting unbound variable STR
#<File stream "/u/neald/trace.txt">
:trace-output
option for the function
fac
to
str
.
fac
function, and then close the file stream as follows:CL-USER 138 > (fac 8)
40320
CL-USER 139 > (close str)
T
Inspect the file
trace.txt
in order to see the trace output for the call of
(fac 8)
.