PUTCHAR_UNLOCKED(3) Library Functions Manual PUTCHAR_UNLOCKED(3)

putchar_unlockedstdio with explicit client locking

#include <stdio.h>

int putchar_unlocked(int c);

Refer to getc_unlocked(3) .

Derived from the POSIX Threads Extension (1003.1c-1995)

February 1997 posix.fail