ICONVCTL(3) GNU ICONVCTL(3)
December 15, 2024
NAME
iconvctl - control iconv behavior
SYNOPSIS
#include <iconv.h>
int iconvctl (iconv_t cd , int request, void * argument
DESCRIPTION
The argument cd must be a conversion descriptor created using the
function iconv_open.
iconvctl queries or adjusts the behavior of the iconv function, when
invoked with the specified conversion descriptor, depending on the
request value.
REQUEST VALUES
The following are permissible values for the request parameter.
ICONV_TRIVIALP
argument should be an int * which will receive 1 if the
conversion is trivial, or 0 otherwise.
ICONV_GET_TRANSLITERATE
argument should be an int * which will receive 1 if
transliteration is enabled in the conversion, or 0 otherwise.
ICONV_SET_TRANSLITERATE
argument should be a const int *, pointing to an int value. A
non-zero value is used to enable transliteration in the
conversion. A zero value disables it.
ICONV_GET_DISCARD_INVALID
argument should be an int * which will receive 1 if "discard
invalid multibyte sequence from the input and continue" is
enabled in the conversion, or 0 otherwise.
ICONV_SET_DISCARD_INVALID
argument should be a const int *, pointing to an int value. A
non-zero value is used to enable "discard invalid multibyte
sequence from the input and continue" in the conversion. A zero
value disables it.
ICONV_GET_DISCARD_NON_IDENTICAL
argument should be an int * which will receive 1 if "discard
character that cannot be represented in the target character set
and continue" is enabled in the conversion, or 0 otherwise.
ICONV_SET_DISCARD_NON_IDENTICAL
argument should be a const int *, pointing to an int value. A
non-zero value is used to enable "discard character that cannot
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December 15, 2024
be represented in the target character set and continue" in the
conversion. A zero value disables it.
ICONV_GET_DISCARD_ILSEQ
argument should be an int * which will receive 1 if both
"discard" behaviours are enabled in the conversion, or 0
otherwise.
ICONV_SET_DISCARD_ILSEQ
argument should be a const int *, pointing to an int value. A
non-zero value is used to enable both "discard" behaviours in the
conversion. A zero value disables them.
ICONV_GET_FROM_SURFACE
argument should be an unsigned int * which will receive the
from-side (input side) surface of the conversion.
ICONV_SET_FROM_SURFACE
argument should be a const unsigned int *, pointing to an
unsigned int value. This value is installed as the from-side
(input side) surface of the conversion. The value is a bit mask.
Zero denotes no surface. The value ICONV_SURFACE_EBCDIC_ZOS_UNIX
has an effect on EBCDIC encodings: The EBCDIC newline 0x15 will
get mapped to LF instead of NEL.
ICONV_GET_TO_SURFACE
argument should be an unsigned int * which will receive the to-
side (output side) surface of the conversion.
ICONV_SET_TO_SURFACE
argument should be a const unsigned int *, pointing to an
unsigned int value. This value is installed as the to-side
(output side) surface of the conversion. The value is a bit
mask. Zero denotes no surface. The value
ICONV_SURFACE_EBCDIC_ZOS_UNIX has an effect on EBCDIC encodings:
LF, instead of NEL, will get mapped to the EBCDIC newline 0x15.
RETURN VALUE
The iconvctl function returns 0 if it succeeds. In case of error, it
sets errno and returns -1.
ERRORS
The following errors can occur, among others:
EINVAL
The request is invalid.
CONFORMING TO
This function is implemented only in GNU libiconv and not in other
iconv implementations. It is not backed by a standard. You can test
for its presence through (_LIBICONV_VERSION >= 0x0108).
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ICONVCTL(3) GNU ICONVCTL(3)
December 15, 2024
SEE ALSO
iconv_open(3) iconv(3)
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