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 XSH 2.2 The Compilation Environment ) to enable the visibility of these symbols in this header.
The <ctype.h> header shall define the locale_t type as described in <locale.h>, representing a locale object.
The following shall be declared as functions and may also be defined as macros. Function prototypes shall be provided for use with ISO C standard compilers.
int isalnum(int); [CX]int isalnum_l(int, locale_t);
int isalpha(int); [CX]
int isalpha_l(int, locale_t);
int isblank(int); [CX]
int isblank_l(int, locale_t);
int iscntrl(int); [CX]
int iscntrl_l(int, locale_t);
int isdigit(int); [CX]
int isdigit_l(int, locale_t);
int isgraph(int); [CX]
int isgraph_l(int, locale_t);
int islower(int); [CX]
int islower_l(int, locale_t);
int isprint(int); [CX]
int isprint_l(int, locale_t);
int ispunct(int); [CX]
int ispunct_l(int, locale_t);
int isspace(int); [CX]
int isspace_l(int, locale_t);
int isupper(int); [CX]
int isupper_l(int, locale_t);
int isxdigit(int); [CX]
int isxdigit_l(int, locale_t);
int tolower(int); [CX]
int tolower_l(int, locale_t);
int toupper(int); [CX]
int toupper_l(int, locale_t);
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XSH 2.2 The Compilation Environment , isalnum , isalpha , isblank , iscntrl , isdigit , isgraph , islower , isprint , ispunct , isspace , isupper , isxdigit , mblen , mbstowcs , mbtowc , setlocale , tolower , toupper , wcstombs , wctomb
First released in Issue 1. Derived from Issue 1 of the SVID.
Extensions beyond the ISO C standard are marked.
SD5-XBD-ERN-6 is applied, updating the wording regarding the function declarations for consistency.
The *_l() functions are added from The Open Group Technical Standard, 2006, Extended API Set Part 4.
Austin Group Defect 1330 is applied, removing obsolescent interfaces.
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