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Update. 

2001-02-08  Andreas Jaeger  <aj@suse.de>

	* manual/stdio.texi (Closing Streams): Fix typos.
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Andreas Jaeger 2001-02-08 09:28:59 +00:00
parent b317de5464
commit f6af7428db
2 changed files with 13 additions and 9 deletions
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4
ChangeLog
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@ -1,3 +1,7 @@
2001-02-08 Andreas Jaeger <aj@suse.de>
* manual/stdio.texi (Closing Streams): Fix typos.
2001-02-07 Ulrich Drepper <drepper@redhat.com> 2001-02-07 Ulrich Drepper <drepper@redhat.com>
* sysdeps/alpha/alphaev67/strncat.S: Align last write address. * sysdeps/alpha/alphaev67/strncat.S: Align last write address.

18
manual/stdio.texi
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@ -372,7 +372,7 @@ see @ref{Stream Buffering}.
In some situations it is useful to know whether a given stream is In some situations it is useful to know whether a given stream is
available for reading or writing. This information is normally not available for reading or writing. This information is normally not
available and would have have to be remembered separately. Solaris available and would have to be remembered separately. Solaris
introduced a few functions to get this information from the stream introduced a few functions to get this information from the stream
descriptor and these functions are also available in the GNU C library. descriptor and these functions are also available in the GNU C library.
@ -388,7 +388,7 @@ This function is declared in @file{stdio_ext.h}.
@comment stdio_ext.h @comment stdio_ext.h
@comment GNU @comment GNU
@deftypefun int __fwritaable (FILE *@var{stream}) @deftypefun int __fwritable (FILE *@var{stream})
The @code{__fwritable} function determines whether the stream The @code{__fwritable} function determines whether the stream
@var{stream} was opened to allow writing. In this case the return value @var{stream} was opened to allow writing. In this case the return value
is nonzero. For read-only streams the function returns zero. is nonzero. For read-only streams the function returns zero.
@ -396,7 +396,7 @@ is nonzero. For read-only streams the function returns zero.
This function is declared in @file{stdio_ext.h}. This function is declared in @file{stdio_ext.h}.
@end deftypefun @end deftypefun
For a slightly different kind of problems there are two more functions. For slightly different kind of problems there are two more functions.
They provide even finer-grained information. They provide even finer-grained information.
@comment stdio_ext.h @comment stdio_ext.h
@ -432,7 +432,7 @@ are used in single-threaded applications. But the programmer must be
aware of a the possible complications. It is important to know about aware of a the possible complications. It is important to know about
these also if the program one writes never use threads since the design these also if the program one writes never use threads since the design
and implementation of many stream functions is heavily influenced by the and implementation of many stream functions is heavily influenced by the
requierements added by multi-threaded programming. requirements added by multi-threaded programming.
The POSIX standard requires that by default the stream operations are The POSIX standard requires that by default the stream operations are
atomic. I.e., issueing two stream operations for the same stream in two atomic. I.e., issueing two stream operations for the same stream in two
@ -455,7 +455,7 @@ perform the stream locking in the application code.
@comment POSIX @comment POSIX
@deftypefun void flockfile (FILE *@var{stream}) @deftypefun void flockfile (FILE *@var{stream})
The @code{flockfile} function acquires the internal locking object The @code{flockfile} function acquires the internal locking object
associated with the stream @var{stream}. This ensure that no other associated with the stream @var{stream}. This ensures that no other
thread can explicitly through @code{flockfile}/@code{ftrylockfile} or thread can explicitly through @code{flockfile}/@code{ftrylockfile} or
implicit through a call of a stream function lock the stream. The implicit through a call of a stream function lock the stream. The
thread will block until the lock is acquired. An explicit call to thread will block until the lock is acquired. An explicit call to
@ -465,7 +465,7 @@ thread will block until the lock is acquired. An explicit call to
@comment stdio.h @comment stdio.h
@comment POSIX @comment POSIX
@deftypefun int ftrylockfile (FILE *@var{stream}) @deftypefun int ftrylockfile (FILE *@var{stream})
The@code{ftrylockfile} function tries to acquire the internal locking The @code{ftrylockfile} function tries to acquire the internal locking
object associated with the stream @var{stream} just like object associated with the stream @var{stream} just like
@code{flockfile}. But unlike @code{flockfile} this function does not @code{flockfile}. But unlike @code{flockfile} this function does not
block if the lock is not available. @code{ftrylockfile} returns zero if block if the lock is not available. @code{ftrylockfile} returns zero if
@ -530,7 +530,7 @@ if the @code{ftrylockfile} function succeeded in locking the stream. It
is therefore always wrong to ignore the result of @code{ftrylockfile}. is therefore always wrong to ignore the result of @code{ftrylockfile}.
And it makes no sense since otherwise one would use @code{flockfile}. And it makes no sense since otherwise one would use @code{flockfile}.
The result of code like that above is that either @code{funlockfile} The result of code like that above is that either @code{funlockfile}
tries to free a stream hasn't been locked by the current thread or it tries to free a stream that hasn't been locked by the current thread or it
frees the stream prematurely. The code should look like this: frees the stream prematurely. The code should look like this:
@smallexample @smallexample
@ -546,7 +546,7 @@ foo (FILE *fp)
@end smallexample @end smallexample
Now that we covered why it is necessary to have these locking it is Now that we covered why it is necessary to have these locking it is
necessary to talk about siuations when locking is unwanted and what can necessary to talk about situations when locking is unwanted and what can
be done. The locking operations (explicit or implicit) don't come for be done. The locking operations (explicit or implicit) don't come for
free. Even if a lock is not taken the cost is not zero. The operations free. Even if a lock is not taken the cost is not zero. The operations
which have to be performed require memory operations which are save in which have to be performed require memory operations which are save in
@ -564,7 +564,7 @@ standard defines quite a few of those and the GNU library adds a few
more. These variants of the functions behave just like the functions more. These variants of the functions behave just like the functions
with the name without the suffix except that they are not locking the with the name without the suffix except that they are not locking the
stream. Using these functions is very desirable since they are stream. Using these functions is very desirable since they are
potentially very much faster. This is not only because the locking potentially much faster. This is not only because the locking
operation itself is avoided. More importantly, functions like operation itself is avoided. More importantly, functions like
@code{putc} and @code{getc} are very simple and tradionally (before the @code{putc} and @code{getc} are very simple and tradionally (before the
introduction of threads) were implemented as macros which are very fast introduction of threads) were implemented as macros which are very fast