deallocate descriptor for character set conversion
Standard C library (libc, -lc)
The iconv_close() function deallocates a conversion descriptor cd previously allocated using iconv_open(3).
On success, iconv_close() returns 0; otherwise, it returns -1 and sets errno to indicate the error.
For an explanation of the terms used in this section, see attributes(7).
POSIX.1-2008.
glibc 2.1. POSIX.1-2001.