.TH "OSMIUM-DIFF" "1" "1.5.1" "" ""
.SH NAME
.PP
osmium\-diff \- display differences between OSM files
.SH SYNOPSIS
.PP
\f[B]osmium diff\f[] [\f[I]OPTIONS\f[]] \f[I]OSM\-FILE1\f[]
\f[I]OSM\-FILE2\f[]
.SH DESCRIPTION
.PP
Finds differences between two OSM files and displays them.
.PP
Only differences between objects (node, ways, and relations) are found
and displayed.
Headers are ignored.
.PP
Objects in both input files must be sorted in the same order.
.PP
Several output formats are supported, see the \f[B]OUTPUT FORMATS\f[]
section.
.PP
This command is intended for displaying the differences between files to
humans.
It can not be used to create an OSM change file (\f[C]\&.osc\f[]), use
\f[B]osmium\-derive\-changes\f[] for that.
.SH OUTPUT FORMATS
.PP
The following output formats are supported and can be set with the
\f[B]\-\-output\-format\f[] or \f[B]\-f\f[] options.
Default is the compact format.
.TP
.B compact
A very compact format.
For all objects a line is printed with the type of object (\[aq]n\[aq],
\[aq]w\[aq], or \[aq]r\[aq]), the object ID and then the version number.
If objects appear in both files and are identical they are preceded by a
space (\[aq] \[aq]) character, if they are in both files, but different,
they are preceded by an asterisk (\[aq]*\[aq]).
Otherwise they get a minus (\[aq]\-\[aq]) or plus (\[aq]+\[aq])
character to show that they are only in the first or second file,
respectively.
.RS
.RE
.TP
.B opl
The usual OPL format with all lines preceded by space (\[aq] \[aq]),
minus (\[aq]\-\[aq]), or plus (\[aq]+\[aq]) characters depending on
whether the object is in both, the first, or the second file.
.RS
.RE
.TP
.B debug
The usual debug format with all lines preceded by space (\[aq] \[aq]),
minus (\[aq]\-\[aq]), or plus (\[aq]+\[aq]) characters depending on
whether the object is in both, the first, or the second file.
Color support can be enabled (\[aq]debug,color\[aq]).
.RS
.RE
.PP
None of the output formats print the headers of the input files.
.SH OPTIONS
.TP
.B \-c, \-\-suppress\-common
Do not output objects that are the same in both files.
.RS
.RE
.TP
.B \-f, \-\-output\-format=FORMAT
See the \f[B]OUTPUT FORMATS\f[] section.
.RS
.RE
.TP
.B \-o, \-\-output=FILE
Name of the output file.
Default is \[aq]\-\[aq] (STDOUT).
.RS
.RE
.TP
.B \-O, \-\-overwrite
Allow an existing output file to be overwritten.
Normally \f[B]osmium\f[] will refuse to write over an existing file.
.RS
.RE
.TP
.B \-q, \-\-quiet
No output.
Just report when files differ through the return code.
.RS
.RE
.TP
.B \-s, \-\-summary
Print count of objects that are only in the left or right files, or the
same in both or different in both to \f[I]stderr\f[].
.RS
.RE
.TP
.B \-t, \-\-object\-type=TYPE
Read only objects of given type (\f[I]node\f[], \f[I]way\f[],
\f[I]relation\f[]).
By default all types are read.
This option can be given multiple times.
This affects the output as well as the return code of the command.
.RS
.RE
.SH COMMON OPTIONS
.TP
.B \-h, \-\-help
Show usage help.
.RS
.RE
.TP
.B \-v, \-\-verbose
Set verbose mode.
The program will output information about what it is doing to
\f[I]stderr\f[].
.RS
.RE
.SH INPUT OPTIONS
.TP
.B \-F, \-\-input\-format=FORMAT
The format of the input file(s).
Can be used to set the input format if it can\[aq]t be autodetected from
the file name(s).
This will set the format for all input files, there is no way to set the
format for some input files only.
See \f[B]osmium\-file\-formats\f[](5) or the libosmium manual for
details.
.RS
.RE
.SH DIAGNOSTICS
.PP
\f[B]osmium diff\f[] exits with exit code
.TP
.B 0
if the files are the same,
.RS
.RE
.TP
.B 1
if the files are different, or
.RS
.RE
.TP
.B 2
if there was an error
.RS
.RE
.SH MEMORY USAGE
.PP
\f[B]osmium diff\f[] doesn\[aq]t keep a lot of data in memory.
.SH EXAMPLES
.PP
Show difference between Nepal files from January 2016 and Febrary 2016
in compact format:
.IP
.nf
\f[C]
osmium\ diff\ nepal\-20160101.osm.pbf\ nepal\-20160201.osm.pbf
\f[]
.fi
.PP
Show in color debug format only those objects that are different:
.IP
.nf
\f[C]
osmium\ diff\ nepal\-20160101.osm.pbf\ nepal\-20160201.osm.pbf\ \-f\ debug,color\ \-c
\f[]
.fi
.SH SEE ALSO
.IP \[bu] 2
\f[B]osmium\f[](1), \f[B]osmium\-file\-formats\f[](5),
\f[B]osmium\-derive\-changes\f[](1)
.IP \[bu] 2
Osmium website (http://osmcode.org/osmium-tool/)
.SH COPYRIGHT
.PP
Copyright (C) 2013\-2017 Jochen Topf <jochen@topf.org>.

License GPLv3+: GNU GPL version 3 or later
<https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
.SH CONTACT
.PP
If you have any questions or want to report a bug, please go to
http://osmcode.org/contact.html
.SH AUTHORS
Jochen Topf <jochen@topf.org>.