iconvconfig — create iconv module configuration cache


iconvconfig [options] [directory...]


The iconv(3) function internally uses gconv modules to convert to and from a character set. A configuration file is used to determine the needed modules for a conversion. Loading and parsing such a configuration file would slow down programs that use iconv(3), so a caching mechanism is employed.

The iconvconfig program reads iconv module configuration files and writes a fast-loading gconv module configuration cache file.

In addition to the system provided gconv modules, the user can specify custom gconv module directories with the environment variable GCONV_PATH. However, iconv module configuration caching is used only when the environment variable GCONV_PATH is not set.



Do not search the system default gconv directory, only the directories provided on the command line.

−o outputfile, −−output=outputfile

Use outputfile for output instead of the system default cache location.


Set the prefix to be prepended to the system pathnames. See FILES, below. By default, the prefix is empty. Setting the prefix to foo, the gconv module configuration would be read from foo/usr/lib/gconv/gconv−modules and the cache would be written to foo/usr/lib/gconv/gconv−modules.cache.

−?, −−help

Print a usage summary and exit.


Print a short usage summary and exit.

−V, −−version

Print the version number, license, and disclaimer of warranty for iconv.


Zero on success, nonzero on errors.



Usual default gconv module path.


Usual system default gconv module configuration file.


Usual system gconv module configuration cache.

Depending on the architecture, the above files may instead be located at directories with the path prefix /usr/lib64.


iconv(1), iconv(3)


This page is part of release 5.13 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at−pages/.

  Copyright (C) 2014 Marko Myllynen <>

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