This documentation is copyright © 1998-2001 Sandro Sigala <sandro@sigala.it>.
All rights reserved.

Released under the GNU General Public License.

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isxdigit

Prototype

#include <ctype.h>

int isxdigit(int c);

Description

Returns a true value if the c character is an hexadecimal-digit character.

Example

View source
#include <ctype.h>

/*
 * Translate the hexadecimal argument string into an integer value.
 */
int hex_to_int(const char *s)
{
    int i = 0;

    for (; *s != '\0'; ++s) {
	if (!isxdigit(*s))
	    return i;
	i *= 16;
	if (isdigit(*s))
	    i += *s - '0';
	else
	    i += tolower(*s) - 'a' + 10;
    }

    return i;
}

References

ISO C 9899:1990 7.3.1.11