ref: d570229e8268c96e97858f021b84bf00305f1daa
dir: /sys/src/libString/s_tolower.c/
#include <u.h>
#include <libc.h>
#include "String.h"
/* convert String to lower case */
void
s_tolower(String *sp)
{
char *cp;
for(cp=sp->ptr; *cp; cp++)
*cp = tolower(*cp);
}