unlocked_stdio (3)
Leading comments
Copyright (C) 2001 Andries Brouwer <aeb@cwi.nl>. %%%LICENSE_START(VERBATIM) Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Since the ...
NAME
getc_unlocked, getchar_unlocked, putc_unlocked, putchar_unlocked - nonlocking stdio functionsSYNOPSIS
#include <stdio.h> int getc_unlocked(FILE *stream); int getchar_unlocked(void); int putc_unlocked(int c, FILE *stream); int putchar_unlocked(int c); 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); char *fgets_unlocked(char *s, int n, FILE *stream); int fputs_unlocked(const char *s, FILE *stream); #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);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
getc_unlocked(), getchar_unlocked(), putc_unlocked(), putchar_unlocked():
- _POSIX_C_SOURCE >= 1 || _XOPEN_SOURCE || _POSIX_SOURCE || _BSD_SOURCE || _SVID_SOURCE
clearerr_unlocked(), feof_unlocked(), ferror_unlocked(), fileno_unlocked(), fflush_unlocked(), fgetc_unlocked(), fputc_unlocked(), fread_unlocked(), fwrite_unlocked():
- _BSD_SOURCE || _SVID_SOURCE
fgets_unlocked(), fputs_unlocked(), getwc_unlocked(), getwchar_unlocked(), fgetwc_unlocked(), fputwc_unlocked(), putwchar_unlocked(), fgetws_unlocked(), fputws_unlocked():
- _GNU_SOURCE
DESCRIPTION
Each of these functions has the same behavior 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).ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).| Interface | Attribute | Value |
| getc_unlocked(), putc_unlocked(), clearerr_unlocked(), fflush_unlocked(), fgetc_unlocked(), fputc_unlocked(), fread_unlocked(), fwrite_unlocked(), fgets_unlocked(), fputs_unlocked(), getwc_unlocked(), fgetwc_unlocked(), fputwc_unlocked(), putwc_unlocked(), fgetws_unlocked(), fputws_unlocked() | Thread safety | MT-Safe race:stream |
| getchar_unlocked(), getwchar_unlocked() | Thread safety | MT-Unsafe race:stdin |
| putchar_unlocked(), putwchar_unlocked() | Thread safety | MT-Unsafe race:stdout |
| feof_unlocked(), ferror_unlocked(), fileno_unlocked() | Thread safety | MT-Safe |
CONFORMING TO
The four functions getc_unlocked(), getchar_unlocked(), putc_unlocked(), putchar_unlocked() are in POSIX.1-2001 and POSIX.1-2008.The nonstandard *_unlocked() variants occur on a few UNIX systems, and are available in recent glibc. They should probably not be used.