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Manual Pages  — KTRDUMP


ktrdump – print kernel ktr trace buffer



ktrdump [-cflqrtH] [-i ktrfile] [-M core] [-N system] [-o outfile]


The ktrdump utility is used to dump the contents of the kernel ktr trace buffer.

The following options are available:
-c Print the CPU number that each entry was logged from.
-l Poll the kernel ktr trace buffer periodically dumping any new events after each poll.
-f Print the file and line number that each entry was logged from.
-q Quiet mode; do not print the column header.
-r Print relative timestamps rather than absolute timestamps.
-t Print the timestamp for each entry.
-H Print the thread ID for each entry.
-i ktrfile
  File containing saved ktr trace events; for more information see the ktr(4) manual page.
-N system
  The kernel image to resolve symbols from. The default is the value returned via getbootfile(3).
-M core
  The core file or memory image to read from. The default is /dev/mem.
-o outfile
  The file to write the output to. The default is standard output.


ktr(4), ktr(9)


The ktrdump utility first appeared in FreeBSD 5.0 .


The ktrdump utility was implemented by Jake Burkholder <Mt jake@FreeBSD.org>.

This manual page was written by Chad David <Mt davidc@FreeBSD.org>.

KTRDUMP (8) October 22, 2018

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