getc_unlocked
int getc_unlocked(FILE *);
#define getchar_unlocked() getc_unlocked(stdin)
while ((ch = getc_unlocked(_gr_fp)) != '\n' &&
while ((ch = getc_unlocked(fp)) != '\n' && ch != EOF)
while ((c = getc_unlocked(tf)) != '\n' && c != EOF)
PROTO_NORMAL(getc_unlocked);
DEF_WEAK(getc_unlocked);
return (getc_unlocked(stdin));
TEST_NARROW(getc_unlocked(f));
c = getc_unlocked(stream);