UNLOCKED_STDIO(3)					     Linux Programmer's Manual						 UNLOCKED_STDIO(3)

NAME

       *_unlocked - non-locking stdio functions

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);

       #define _BSD_SOURCE /* or _SVID_SOURCE or _GNU_SOURCE */
       #include <stdio.h>

       void clearerr_unlocked(FILE *stream);
       int feof_unlocked(FILE *stream);
       int ferror_unlocked(FILE *stream);
       int fileno_unlocked(FILE *stream);
       int fflush_unlocked(FILE *stream);
       int fgetc_unlocked(FILE *stream);
       int fputc_unlocked(int c, FILE *stream);
       size_t fread_unlocked(void *ptr, size_t size, size_t n,
	 FILE *stream);
       size_t fwrite_unlocked(const void *ptr, size_t size, size_t n,
	 FILE *stream);

       #define _GNU_SOURCE
       #include <stdio.h>

       char *fgets_unlocked(char *s, int n, FILE *stream);
       int fputs_unlocked(const char *s, FILE *stream);

       #define _GNU_SOURCE
       #include <wchar.h>

       wint_t getwc_unlocked(FILE *stream);
       wint_t getwchar_unlocked(void);
       wint_t fgetwc_unlocked(FILE *stream);
       wint_t fputwc_unlocked(wchar_t wc, FILE *stream);
       wint_t putwc_unlocked(wchar_t wc, FILE *stream);
       wint_t putwchar_unlocked(wchar_t wc);
       wchar_t *fgetws_unlocked(wchar_t *ws, int n, FILE *stream);
       int fputws_unlocked(const wchar_t *ws, FILE *stream);

DESCRIPTION

       Each of these functions has the same behaviour as its counterpart without the `_unlocked' suffix, except that they do not use locking (they
       do not set locks themselves, and do not test for the presence of locks set by others) and hence are thread-unsafe.  See flockfile(3).

CONFORMING TO

       The four functions getc_unlocked(), getchar_unlocked(), putc_unlocked(), putchar_unlocked() are in POSIX.1.  The  nonstandard  *_unlocked()
       variants occur on a few Unix systems, and are available in recent glibc.  They should probably not be used.

SEE ALSO

       flockfile(3)

								    2001-10-18							 UNLOCKED_STDIO(3)