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KDUMP(1)                    General Commands Manual                   KDUMP(1)

     kdump - display kernel trace data

     kdump [-dElNnRT] [-e emulation] [-f file] [-m maxdata] [-p pid]
           [-t trstr] [-x | -X size] [file]

     kdump displays the kernel trace files produced with ktrace(1) in human
     readable format.  The file ktrace.out in the current directory is
     displayed, unless either the -f option is used, or a file name is
     supplied as the last argument.

     The options are as follows:

     -d          Display all numbers in decimal.

     -E          Display elapsed timestamps (time since beginning of trace).

     -e emulation
                 If an emulation of a process is unknown, interpret system
                 call maps assuming the named emulation instead of default

     -f file     Display the specified file instead of ktrace.out.

     -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 system call number-to-name translation.

     -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      Only display records from the trace file that are for the
                 indicated pid.

     -R          Display relative timestamps (time since previous entry).

     -T          Display absolute timestamps for each entry (seconds since

     -t trstr    Restrict display to the specified set of kernel trace points.
                 The default is to display everything in the file.  See the -t
                 option of ktrace(1).

     -x          Display GIO data in hex and ascii instead of vis(3) format.

     -X size     Same as -x but display hex values by groups of size bytes.
                 Supported values are 1, 2, 4, 8, and 16.

     ioctlprint(1), ktrace(1)

     The kdump command appeared in 4.4BSD.

NetBSD 9.99                      April 2, 2020                     NetBSD 9.99