ctype.h - character types
#include <ctype.h>
[CX] Some of the functionality described on this reference page extends the ISO C standard. Applications shall define the appropriate feature test macro (see the System Interfaces volume of IEEE Std 1003.1-2001, Section 2.2, The Compilation Environment) to enable the visibility of these symbols in this header.The following shall be declared as functions and may also be defined as macros. Function prototypes shall be provided.
int isalnum(int); int isalpha(int); [XSI] int isascii(int); int isblank(int); int iscntrl(int); int isdigit(int); int isgraph(int); int islower(int); int isprint(int); int ispunct(int); int isspace(int); int isupper(int); int isxdigit(int); [XSI] int toascii(int); int tolower(int); int toupper(int);The following are defined as macros:
[XSI] int _toupper(int); int _tolower(int);
None.
None.
None.
<locale.h>, the System Interfaces volume of IEEE Std 1003.1-2001, isalnum(), isalpha(), isascii(), iscntrl(), isdigit(), isgraph(), islower(), isprint(), ispunct(), isspace(), isupper(), isxdigit(), mblen(), mbstowcs(), mbtowc(), setlocale(), toascii(), tolower(), _tolower(), toupper(), _toupper(), wcstombs(), wctomb()
First released in Issue 1. Derived from Issue 1 of the SVID.
Extensions beyond the ISO C standard are marked.