strlwr.c

来自「KPIT GNU Tools is a set of GNU developme」· C语言 代码 · 共 51 行

/*
FUNCTION
	<<strlwr>>---force string to lowercase
	
INDEX
	strlwr

ANSI_SYNOPSIS
	#include <string.h>
	char *strlwr(char *<[a]>);

TRAD_SYNOPSIS
	#include <string.h>
	char *strlwr(<[a]>)
	char *<[a]>;

DESCRIPTION
	<<strlwr>> converts each character in the string at <[a]> to
	lowercase.

RETURNS
	<<strlwr>> returns its argument, <[a]>.

PORTABILITY
<<strlwr>> is not widely portable.

<<strlwr>> requires no supporting OS subroutines.

QUICKREF
	strlwr
*/

#include <string.h>
#include <ctype.h>

char *
strlwr (a)
     char *a;
{
  char *ret = a;

  while (*a != '\0')
    {
      if (isupper (*a))
	*a = tolower (*a);
      ++a;
    }

  return ret;
}