iconv_open - Open a character codeset converter
const char *tocode,
const char *fromcode );
The iconv library (libiconv)
Interfaces documented on this reference page conform to
industry standards as follows:
Refer to the standards(5) reference page for more information
about industry standards and associated tags.
Specifies the destination codeset. Specifies the originating
The iconv_open() function initializes a codeset converter.
This converter is used by the iconv function to convert
characters from one codeset to another. The iconv_open()
function finds the converter that performs the character
conversion specified by the fromcode and tocode parameters,
initializes that converter, then returns a conversion
descriptor of type iconv_t that identifies the converter.
The conversion descriptor returned by this function
remains valid until the descriptor is closed for the process
in which the application is run. The descriptor can
be closed by an iconv_close() call in which the descriptor
is an argument or by a call to one of the exec() functions.
Note that standards do not define where codeset converters
reside or how vendors implement them.
[Tru64 UNIX] The iconv_open() codesets, the function then
searches for a table converter. The algorithmic and table
converter file names are formed by concatenating the
tocode parameter codeset name onto the fromcode parameter
codeset name, with an underscore between the two, for
fromcode=ct tocode=ISO8859-1 Converter name=ct_ISO8859-1
[Tru64 UNIX] The iconv_open() function searches for an
algorithmic converter in an iconv subdirectory of the
directory specified in the LOCPATH environment variable.
The function searches for a table converter in an iconvTable
subdirectory of the directory specified in the LOCPATH
environment variable. If LOCPATH is not defined,
iconv_open() uses the default value: /usr/lib/nls/loc.
[Tru64 UNIX] The LOCPATH variable also overrides the
default search path (/usr/lib/nls/loc) that is used to
find locales. If this variable is defined, it must therefore
specify a search path that application and system
software can use to find both locales and converters. The
LOCPATH variable is not defined by any standard, so use of
the variable should be limited to testing locales or converters
On successful completion, the iconv_open() function
returns a conversion descriptor. Otherwise, the function
returns -1 cast to iconv_t and sets errno to indicate the
If any of the following conditions occur, the iconv_open()
function sets errno to the corresponding value: The number
of file descriptors specified by the OPEN_MAX configuration
variable is currently open in the calling process.
[Tru64 UNIX] Either the OPEN_MAX value or the perprocess
soft descriptor limit is checked. [Tru64
UNIX] The path used to find the codeset converter
is longer than PATH_MAX. Too many files are currently
open in the system. Insufficient virtual
memory is available. The conversion specified by
the fromcode and tocode parameters is not supported.
[Tru64 UNIX] This condition may also indicate an
incorrect LOCPATH setting because support for the
specified conversion is determined by finding a
converter whose name also specifies that conversion.
Commands: genxlt(1), iconv(1)
Functions: iconv(3), iconv_close(3)
Others: iconv_intro(5), standards(5)
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