The xtt command is a debugging tool for the
driver. It performs an XTIOCTRACEioctl(S)
call on its standard input file to turn on tracing and extract the
circular packet trace buffer for the attached group of channels.
This call will fail if tracing has not been configured in the driver,
or the standard input is not attached to an
The packets are printed on the standard output.
The optional flags are:
Causes a ``formfeed'' character to be put out at the end of the output
for the benefit of page-display programs.
Turns off further driver tracing.
Returns 0 upon successful completion; 1 otherwise.
If driver tracing has not been turned on for the
terminal session by invoking
with the -t option, xtt will not generate any output
the first time it is executed.