a simple function to duplicate string and upper it.

strdup_upper.c

/*
a simple function to duplicate string and upper it.

sample:

...
char *upper = strdup_upper("HELLO world");
if (!upper) { perror("ops!"); exit(1); }
puts(upper);
free(upper);
...

*/

char* strdup_upper(char* str) {
	char *b;
	char *s;
	char *buf;
	
	errno = 0;
	buf = strdup(str);
	if (!buf)
		return NULL;

	b = buf;
	s = str;
	while(*b) {
		*b++ = toupper(*s++);
	}

	errno = 0;
	return buf;
}