KDUMP(1)

NAME
kdump - display kernel trace data

SYNOPSIS
kdump [-dHlnRTXx] [-f file] [-m maxdata] [-P program] [-p pid] [-t trstr] [-u label]

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 program
    Show output only for processes with program as their command name.

-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 following letters. By default all trace points except for X are enabled.

    c   trace system calls
    i   trace I/O
    n   trace namei translations
    p   trace violation of pledge(2) restrictions
    s   trace signal processing
    S   trace violation of pinsyscalls(2)
    t   trace various structures
    u   trace user data coming from utrace(2)
    x   trace argument vector in execve(2)
    X   trace environment in execve(2)
    +   trace the default points

-u label
    Display utrace(2) tracepoints having utrace(2) label label as strings with vis(3) escaping, without ktrace(2) header information.

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

-x  Display I/O data in hexadecimal.

The -t and -u options are mutually exclusive; the last one specified overrides any previous ones.

FILES
ktrace.out
    default ktrace dump file

SEE ALSO
ktrace(1)

HISTORY
The kdump command appeared in 4.3BSD Reno.