интерфейсы к структуре stdio FILE (interfaces to stdio FILE structure)
Имя (Name)
__fbufsize, __flbf, __fpending, __fpurge, __freadable,
__freading, __fsetlocking, __fwritable, __fwriting, _flushlbf -
interfaces to stdio FILE structure
Синопсис (Synopsis)
#include <stdio.h>
#include <stdio_ext.h>
size_t __fbufsize(FILE *stream);
size_t __fpending(FILE *stream);
int __flbf(FILE *stream);
int __freadable(FILE *stream);
int __fwritable(FILE *stream);
int __freading(FILE *stream);
int __fwriting(FILE *stream);
int __fsetlocking(FILE *stream, int type);
void _flushlbf(void);
void __fpurge(FILE *stream);
Описание (Description)
Solaris introduced routines to allow portable access to the
internals of the FILE structure, and glibc also implemented
these.
The __fbufsize() function returns the size of the buffer
currently used by the given stream.
The __fpending() function returns the number of bytes in the
output buffer. For wide-oriented streams the unit is wide
characters. This function is undefined on buffers in reading
mode, or opened read-only.
The __flbf() function returns a nonzero value if the stream is
line-buffered, and zero otherwise.
The __freadable() function returns a nonzero value if the stream
allows reading, and zero otherwise.
The __fwritable() function returns a nonzero value if the stream
allows writing, and zero otherwise.
The __freading() function returns a nonzero value if the stream
is read-only, or if the last operation on the stream was a read
operation, and zero otherwise.
The __fwriting() function returns a nonzero value if the stream
is write-only (or append-only), or if the last operation on the
stream was a write operation, and zero otherwise.
The __fsetlocking() function can be used to select the desired
type of locking on the stream. It returns the current type. The
type argument can take the following three values:
FSETLOCKING_INTERNAL
Perform implicit locking around every operation on the
given stream (except for the *_unlocked ones). This is
the default.
FSETLOCKING_BYCALLER
The caller will take care of the locking (possibly using
flockfile(3) in case there is more than one thread), and
the stdio routines will not do locking until the state is
reset to FSETLOCKING_INTERNAL.
FSETLOCKING_QUERY
Don't change the type of locking. (Only return it.)
The _flushlbf() function flushes all line-buffered streams.
(Presumably so that output to a terminal is forced out, say
before reading keyboard input.)
The __fpurge() function discards the contents of the stream's
buffer.
Атрибуты (Attributes)
For an explanation of the terms used in this section, see
attributes(7).
┌──────────────────────────┬───────────────┬─────────────────────┐
│Interface │ Attribute │ Value │
├──────────────────────────┼───────────────┼─────────────────────┤
│__fbufsize(), │ Thread safety │ MT-Safe race:stream │
│__fpending(), __fpurge(), │ │ │
│__fsetlocking() │ │ │
├──────────────────────────┼───────────────┼─────────────────────┤
│__flbf(), __freadable(), │ Thread safety │ MT-Safe │
│__freading(), │ │ │
│__fwritable(), │ │ │
│__fwriting(), _flushlbf() │ │ │
└──────────────────────────┴───────────────┴─────────────────────┘
Смотри также (See also)
flockfile(3), fpurge(3)
