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C251 User's Guide

C251 Introduction Compiling Programs Language Extensions Preprocessor Advanced Programming Error Messages Library Reference Library Files Source Code Standard Types jmp_buf va_list Macros CBYTE CVAR CARRAY DARRAY DBYTE DVAR HARRAY HBYTE HVAR NARRAY NBYTE NVAR XARRAY XBYTE XVAR Routines by Category Buffer Manipulation Routines Character Routines Data Conversion Routines Intrinsic Routines Math Routines Memory Allocation Routines Stream I/O Routines String Routines Variable Length Argument Routines Miscellaneous Routines Include Files SFR Definitions absacc.h assert.h ctype.h float.h intrins.h limits.h math.h setjmp.h stdarg.h stddef.h stdio.h stdlib.h string.h Reference _chkdouble_ _chkfloat_ _crol_ _cror_ _getkey _irol_ _iror_ _lrol_ _lror_ _nop_ _testbit_ _tolower _toupper abs acos asin assert atan atan2 atof atoi atol cabs calloc ceil cos cosh exp fabs fcalloc ffree finit_mempool floor fmalloc fmemcpy fmemset frealloc free getchar gets hmemccpy hmemchr hmemcmp hmemcpy hmemmove hmemset hstrcmp hstrcpy hstrlen hstrncpy init_mempool isalnum isalpha iscntrl isdigit isgraph islower isprint ispunct isspace isupper isxdigit labs log log10 longjmp malloc memccpy memchr memcmp memcpy memmove memset modf offsetof pow printf putchar puts rand realloc scanf setjmp sin sinh sprintf sqrt srand sscanf strcat strchr strcmp strcpy strcspn strlen strncat strncmp strncpy strpbrk strpos strrchr strrpbrk strrpos strspn tan tanh toascii toint tolower toupper ungetchar va_arg va_end va_start vprintf vsprintf xcalloc xfree xinit_mempool xmalloc xmemcpy xmemset xrealloc Appendix

Character Routines

The character routines allow you to test individual characters for a variety of attributes and convert characters to different formats.

Routine Attributes Description
isalnum reentrant Tests for an alphanumeric character.
isalpha reentrant Tests for an alphabetic character.
iscntrl reentrant Tests for a Control character.
isdigit reentrant Tests for a decimal digit.
isgraph reentrant Tests for a printable character with the exception of space.
islower reentrant Tests for a lowercase alphabetic character.
isprint reentrant Tests for a printable character.
ispunct reentrant Tests for a punctuation character.
isspace reentrant Tests for a whitespace character.
isupper reentrant Tests for an uppercase alphabetic character.
isxdigit reentrant Tests for a hexadecimal digit.
toascii reentrant Converts a character to an ASCII code.
toint reentrant Converts a hexadecimal digit to a decimal value.
tolower reentrant Tests a character and converts it to lowercase if it is uppercase.
_tolower reentrant Unconditionally converts a character to lowercase.
toupper reentrant Tests a character and converts it to uppercase if it is lowercase.
_toupper reentrant Unconditionally converts a character to uppercase.

The _tolower, _toupper, and toascii routines are implemented as macros. All other routines are implemented as functions. All macro definitions and function prototypes are found in the ctype.h include file.

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