__sputc
#define putc(x, fp) (!__isthreaded ? __sputc(x, fp) : (putc)(x, fp))
#define fputc_unlocked(s, p) __sputc(s, p)
#define putc_unlocked(x, fp) __sputc(x, fp)
return (__sputc(c, fp));
if (__sputc((unsigned char)buf[i], fp) == EOF)
retval = __sputc(c, fp);
return (__sputc(ch, fp));
retval = __sputc(c, so);
return (__sputc(ch, stdout));
ret = __printf(fmt, __sputc, &sp, ap);
static int __sputc(char c, void *arg);