towlowerint

towlowerint is not a standard function in the C language or its common libraries. If you encounter this name in code, it is usually a project-specific symbol, an internal helper, or potentially a misspelling of a standard function such as towlower or tolower. There is no portable, widely recognized function by the exact name towlowerint in ISO C or POSIX.

In standard C, the wide-character equivalent of tolower is towlower, declared in <wchar.h> with the prototype wint_t towlower(wint_t wc). This function maps the wide character wc to its lowercase counterpart according to the LC_CTYPE category of the current locale. If wc has no lowercase mapping, towlower typically returns wc unchanged. The operation is locale-aware and focuses on wide characters represented by wint_t.

Locale-specific variants exist in some libraries. For example, towlower_l may be provided to perform the same mapping using an explicit locale object (locale_t), rather than the global C locale. Such functions are not part of the minimum ISO C standard but are common in newer C libraries (often in POSIX-compatible environments).

Relation to other case-mapping functions: tolower converts single-byte characters (int ch) to lowercase, according to the current locale, while towlower operates on wide characters. In C++, similar functionality is available through <cwctype> with towlower.

If you see towlowerint in your codebase, the prudent step is to check the surrounding headers and build system to determine its actual declaration and intent. It is likely intended as a wrapper, alias, or internal helper, rather than a standard, portable API. For portable wide-character case mapping, use towlower or the library’s locale-aware variant if available.