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uncrustify - C, C++, C#, D, Java and Pawn source code beautifier


uncrustify [OPTIONS] [FILES]


If no input files are specified, the input is read from stdin.
If reading from stdin, you should specify the language using -l.

If -F is used or files are specified on the command line, the output filename is PFX + "/" + filename + SFX.
Unless, of course, the options --replace or --no-backup are used.

When reading from stdin or doing a single file via the '-f' option, the output is dumped to stdout, unless redirected with -o FILE.

Errors are always dumped to stderr


Basic Options:

Use the config file CFG, or defaults if CFG is set to '-'.
If not specified, uncrustify will use $UNCRUSTIFY_CONFIG or $HOME/.uncrustify.cfg.
Process the single file FILE, sending output to stdout or the file specified with -o.
Redirect output to FILE.
Use with -f, --update-config, --update-config-with-doc, --universalindent.
Do not output the new text, instead verify that nothing changes when the file(s) are processed. The status of every file is printed to stderr. The exit code is EXIT_SUCCESS if there were no changes, EXIT_FAILURE otherwise.
Read files to process from FILE, one filename per line. If FILE is ´-´ then read filenames from standard input instead of a file.
You can create this file using something like ´find . -name "*.c" > list.txt´.
This cannot be combined with -f.
Prepend PFX to the output filename path.
This cannot be combined with -f, --replace, or --no-backup.
Append SFX to the output filename.
The default is '.uncrustify' if neither SFX or PFX are specified.
This cannot be combined with -f, --replace, or --no-backup.
Assume the input is a code fragment and the first line is properly indented.
Replace source files (creates a backup).
This cannot be combined with -f, --prefix, or --suffix.
Replace files, no backup. Useful if files are under source control
This cannot be combined with -f, --prefix, or --suffix.
Preserve mtime on replaced files.
Language override: C, CPP, D, CS, JAVA, PAWN, VALA, OC, OC+
Load a file with types (usually not needed)
Quiet mode - no output on stderr (-L will override)

Config/Help Options:

Print this message and exit
Print the version and exit
Print the number of available options and exit
Print out option documentation and exit
Output a new config file.
Output a new config file with embedded usage comments.
Output a config file for Universal Indent GUI.
Detects the config from a source file. Use with '-f FILE'. Detection is currently fairly limited.

Debug Options:

Dump debug info into FILE, or to stdout if FILE is set to '-'.
Must be used in combination with '-f FILE'.
Dump parsing info at various moments of the formatting process.
This creates a series of files named 'FILE_nnn.log', each
corresponding to a formatting step in uncrustify.
The file 'FILE_000.log' lists the formatting options in use.
Must be used in combination with '-f FILE'.
Set the log severity (see log_levels.h)
Show the log severity in the logs
Print FLAG as text and exit


cat foo.d | uncrustify -q -c my.cfg -l d
uncrustify -c my.cfg -d foo.d
find src -name "*.[ch]" > files.txt
uncrustify -c my.cfg -F files.txt --prefix out
uncrustify -c my.cfg --no-backup $(find src -name "*.[ch]")


Use comments containing ' *INDENT-OFF*' and ' *INDENT-ON*' to disable processing of parts of the source file.


Written by Ben Gardner


Use the issue tracker at <>


Copyright (C) 2006‐2014 Ben Gardner
Copyright (C) 2015, 2016 Guy Maurel


GNU GPL version 2 or later <>

This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Oct 2014 uncrustify