putchar_unlocked
Synopsis
#include <stdio.h>
int getc_unlocked(FILE *stream);
int getchar_unlocked(void);
int putc_unlocked(int c, FILE *stream);
int putchar_unlocked(int c);
Status
Partially implemented
Conformance
IEEE Std 1003.1-2017
Description
Versions of the functions getc(), getchar(), putc(), and putchar() respectively named getc_unlocked(),
getchar_unlocked(),putc_unlocked(), and putchar_unlocked() shall be provided which are functionally equivalent to
the original versions, with the exception that they are not required to be implemented in a fully thread-safe manner.
They shall be thread-safe when used within a scope protected by flockfile() (or ftrylockfile()) and funlockfile().
These functions can safely be used in a multithreaded program if and only if they are called while the invoking thread
owns the ( FILE *) object, as is the case after a successful call to the flockfile() or ftrylockfile() functions.
If getc_unlocked() or putc_unlocked() are implemented as macros they may evaluate stream more than once, so
the stream argument should never be an expression with side effects.
Return value
See getc(), getchar(), putc(), and putchar().
Errors
See getc(), getchar(), putc(), and putchar().
Tests
Untested
Known bugs
None