diff options
Diffstat (limited to 'manual/filesys.texi')
| -rw-r--r-- | manual/filesys.texi | 34 |
1 files changed, 33 insertions, 1 deletions
diff --git a/manual/filesys.texi b/manual/filesys.texi index 0f27cfc..3f62aa1 100644 --- a/manual/filesys.texi +++ b/manual/filesys.texi @@ -1811,6 +1811,38 @@ This is the file type constant of a socket. This is the file type constant of a FIFO or pipe. @end table +The POSIX.1b standard introduced a few more objects which possibly can +be implemented as object in the filesystem. These are message queues, +semaphores, and shared memory objects. To allow differentiating these +objects from other files the POSIX standard introduces three new test +macros. But unlike the other macros it does not take the value of the +@code{st_mode} field as the parameter. Instead they expect a pointer to +the whole @code{struct stat} structure. + +@comment sys/stat.h +@comment POSIX +@deftypefn Macro int S_TYPEISMQ (struct stat @var{s}) +If the system implement POSIX message queues as distinct objects and the +file is a message queue object, this macro returns a non-zero value. +In all other cases the result is zero. +@end deftypefn + +@comment sys/stat.h +@comment POSIX +@deftypefn Macro int S_TYPEISSEM (struct stat @var{s}) +If the system implement POSIX semaphores as distinct objects and the +file is a semaphore object, this macro returns a non-zero value. +In all other cases the result is zero. +@end deftypefn + +@comment sys/stat.h +@comment POSIX +@deftypefn Macro int S_TYPEISSHM (struct stat @var{s}) +If the system implement POSIX shared memory objects as distinct objects +and the file is an shared memory object, this macro returns a non-zero +value. In all other cases the result is zero. +@end deftypefn + @node File Owner @subsection File Owner @cindex file owner @@ -2558,7 +2590,7 @@ The operation was interrupted by a signal. @deftypefun int truncate64 (const char *@var{name}, off64_t @var{length}) This function is similar to the @code{truncate} function. The difference is that the @var{length} argument is 64 bits wide even on 32 -bits machines, which allows the handling of files with sizes up to +bits machines, which allows the handling of files with sizes up to @math{2^63} bytes. When the source file is compiled with @code{_FILE_OFFSET_BITS == 64} on a |