osmium-merge-changes (1)

NAME

osmium-merge-changes - merge several OSM change files into one

SYNOPSIS

osmium merge-changes [OPTIONS] OSM-CHANGE-FILE…

DESCRIPTION

Merges the content of all change files given on the command line into one large change file.

Objects are sorted by type, ID, version, and timestamp so it doesn’t matter in what order the change files are given or in what order they contain the data. (If you are using change files of extracts this is not necessarily true and you must specify the change files on the command line in the correct order from oldest to newest. This is because change files from extracts can contain multiple different object versions with the same version and timestamp!)

This commands reads its input file(s) only once and writes its output file in one go so it can be streamed, ie. it can read from STDIN and write to STDOUT.

OPTIONS

-s, --simplify: Only write the last version of any object to the output. For an object created in one of the change files and removed in a later one, the deleted version of the object will still appear because it is the latest version.

COMMON OPTIONS

-h, --help: Show usage help.
-v, --verbose: Set verbose mode. The program will output information about what it is doing to STDERR.
--progress: Show progress bar. Usually a progress bar is only displayed if STDOUT and STDERR are detected to be TTY. With this option a progress bar is always shown. Note that a progress bar will never be shown when reading from STDIN or a pipe.
--no-progress: Do not show progress bar. Usually a progress bar is displayed if STDOUT and STDERR are detected to be a TTY. With this option the progress bar is suppressed. Note that a progress bar will never be shown when reading from STDIN or a pipe.

INPUT OPTIONS

-F, --input-format=FORMAT: The format of the input file(s). Can be used to set the input format if it can’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 osmium-file-formats(5) or the libosmium manual for details.

OUTPUT OPTIONS

-f, --output-format=FORMAT: The format of the output file. Can be used to set the output file format if it can’t be autodetected from the output file name. See osmium-file-formats(5) or the libosmium manual for details.
--fsync: Call fsync after writing the output file to force flushing buffers to disk.
--generator=NAME: The name and version of the program generating the output file. It will be added to the header of the output file. Default is “osmium/” and the version of osmium.
-o, --output=FILE: Name of the output file. Default is ‘-’ (STDOUT).
-O, --overwrite: Allow an existing output file to be overwritten. Normally osmium will refuse to write over an existing file.
--output-header=OPTION=VALUE: Add output header option. This command line option can be used multiple times for different OPTIONs. See the osmium-output-headers(5) man page for a list of available header options. For some commands you can use the special format “OPTION!” (ie. an exclamation mark after the OPTION and no value set) to set the value to the same as in the input file.

DIAGNOSTICS

osmium merge-changes exits with exit code

0: if everything went alright,
1: if there was an error processing the data, or
2: if there was a problem with the command line arguments.

MEMORY USAGE

osmium merge-changes keeps the contents of all the change files in main memory. This will take roughly 10 times as much memory as the files take on disk in .osm.bz2 format.

EXAMPLES

Merge all changes in changes directory into all.osc.gz:

osmium merge-changes -o all.osc.gz changes/*.gz

Because osmium merge-changes sorts its input, you can also use it to sort just a single change file:

osmium merge-changes unsorted.osc.gz -o sorted.osc.gz