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NAME

kdump — display kernel trace data

SYNOPSIS

DESCRIPTION

kdump displays the kernel trace files produced with ktrace(1) in human-readable format. By default, the file ktrace.out in the current directory is displayed, unless overridden by the -f option.

The options are as follows:

-d

Display all numbers in decimal. By default, values are printed out in hexadecimal.

-f file

Display the specified file instead of ktrace.out. Specifying ‘-’ will read from standard input.

-H

Display thread identifiers.

-l

Loop reading the trace file, once the end-of-file is reached, waiting for more data.

-m maxdata

Display at most maxdata bytes when decoding I/O.

-n

Suppress ad hoc translations. Normally kdump tries to decode many system calls into a more human-readable format. For example, ioctl(2) values are replaced with the macro name and errno values are replaced with the strerror(3) string. Suppressing this feature yields a more consistent output format and is easily amenable to further processing.

-p pid

Show output only for the pid specified.

-R

Display relative timestamps (time since previous entry).

-T

Display absolute timestamps for each entry (seconds since the Epoch).

-TR

If both options are specified, display timestamps relative to trace start.

-t trstr

Select which tracepoints to display. The argument can contain one or more of the letters cinpstuxX+. See the -t option of ktrace(1) for the meaning of the letters.

-X

Display I/O data with hexadecimal data and printable ASCII characters side by side.

-x

Display I/O data in hexadecimal.

FILES

ktrace.out

default ktrace dump file

SEE ALSO

ktrace(1)

HISTORY

The kdump command appeared in 4.3BSD-Reno.