.\" As its sole author, I explicitly place this file in the public domain.
.\" It may be used by anyone in any way for any purpose, though I would
.\" appreciate credit where it's due.
.\"		der Mouse, mouse@rodents.montreal.qc.ca, 1999-09-04
.Dd October 23, 2007
.Dt KTRMERGE 1
.Os NetBSD 1.4T
.Sh NAME
.Nm ktrmerge
.Nd ktrace data file merging
.Sh SYNOPSIS
.Nm
.Op Ar file ...
.Sh DESCRIPTION
.Nm
reads multiple
.Xr ktrace 1
output files, collating the trace records within them in chronological
order according to their embedded timestamps, writing the merged data
stream to the standard output.
.Pp
There are no options; all arguments are taken as naming data files.
However, as insurance against problems in case options are added in the
future, it is a good idea to make sure no arguments begin with dashes.
.Pp
The merge algorithm assumes that each input file has its records
correctly ordered by timestamp; if this is not so, the output will have
similar disorder.  Regardless of the timestamps, the output record
stream will be the input record streams merged in some order; that is,
whenever two records in the output come from the same input file, the
one that occurs earlier in the input will be the one that occurs
earlier in the output.
.Pp
Any partial record at the end of an input file will get dropped, with a
warning message to standard error.
.Pp
The input filenames do not need to name plain files; anything that can
be opened and read as a byte-stream will do.  In particular, they do
not need to be seekable or mmappable.
.Pp
Malformatted input (that is, input that does not consist of a valid
stream of
.Xr ktrace 1
records) can, and usually will, cause trouble (most likely, a memory
allocation failure).
.Sh SEE ALSO
.Xr ktrace 1 ,
.Xr kdump 1
.Sh AUTHOR
der Mouse,
.Aq mouse@rodents.montreal.qc.ca .