diff options
Diffstat (limited to 'manual')
| -rw-r--r-- | manual/filesys.texi | 21 | ||||
| -rw-r--r-- | manual/resource.texi | 49 |
2 files changed, 66 insertions, 4 deletions
diff --git a/manual/filesys.texi b/manual/filesys.texi index 84c9f6b8a3..ccc8d55f24 100644 --- a/manual/filesys.texi +++ b/manual/filesys.texi @@ -115,7 +115,7 @@ software. @comment unistd.h @comment BSD -@deftypefun {char *} getwd (char *@var{buffer}) +@deftypefn {Deprecated Function} {char *} getwd (char *@var{buffer}) This is similar to @code{getcwd}, but has no way to specify the size of the buffer. The GNU library provides @code{getwd} only for backwards compatibility with BSD. @@ -125,6 +125,21 @@ The @var{buffer} argument should be a pointer to an array at least system there is no limit to the size of a file name, so this is not necessarily enough space to contain the directory name. That is why this function is deprecated. +@end deftypefn + +@comment unistd.h +@comment GNU +@deftypefun {char *} get_current_dir_name (void) +@vindex PWD +This @code{get_current_dir_name} function is bascially equivalent to +@w{@code{getcwd (NULL, 0)}}. The only difference is that the value of +the @code{PWD} variable is returned if this value is correct. This is a +subtle difference which is visible if the path described by the +@code{PWD} value is using one or more symbol links in which case the +value returned by @code{getcwd} can resolve the symbol links and +therefore yield a different result. + +This function is a GNU extension. @end deftypefun @comment unistd.h @@ -279,8 +294,8 @@ This returns the @code{st_mode} value corresponding to @var{dtype}. This structure may contain additional members in the future. Their availability is always announced in the compilation environment by a -macro names @code{_DIRENT_HAVE_D_xxx} where @code{xxx} is replaced by -the name of the new member. For instance, the member @code{d_reclen} +macro names @code{_DIRENT_HAVE_D_@var{xxx}} where @var{xxx} is replaced +by the name of the new member. For instance, the member @code{d_reclen} available on some systems is announced through the macro @code{_DIRENT_HAVE_D_RECLEN}. diff --git a/manual/resource.texi b/manual/resource.texi index 9fc8b6494b..f9f2e7c3d8 100644 --- a/manual/resource.texi +++ b/manual/resource.texi @@ -1353,7 +1353,8 @@ information about the physical memory the system has. The call sysconf (_SC_PHYS_PAGES) @end smallexample -@noindent returns the total number of page of physical the system has. +@noindent +returns the total number of pages of physical the system has. This does not mean all this memory is available. This information can be found using @@ -1371,6 +1372,31 @@ increases its memory usage). The value returned for If all applications together constantly use more than that amount of memory the system is in trouble. +The GNU C library provides in addition to these already described way to +get this information two functions. They are declared in the file +@file{sys/sysinfo.h}. Programmers should prefer to use the +@code{sysconf} method described above. + +@comment sys/sysinfo.h +@comment GNU +@deftypefun long int get_phys_pages (void) +The @code{get_phys_pages} function returns the total number of pages of +physical the system has. To get the amount of memory this number has to +be multiplied by the page size. + +This function is a GNU extension. +@end deftypefun + +@comment sys/sysinfo.h +@comment GNU +@deftypefun long int get_avphys_pages (void) +The @code{get_phys_pages} function returns the number of available pages of +physical the system has. To get the amount of memory this number has to +be multiplied by the page size. + +This function is a GNU extension. +@end deftypefun + @node Processor Resources @section Learn about the processors available @@ -1402,6 +1428,27 @@ processors and so the call returns the number of processors which are currently inline (i.e., available). +For these two pieces of information the GNU C library also provides +functions to get the information directly. The functions are declared +in @file{sys/sysinfo.h}. + +@comment sys/sysinfo.h +@comment GNU +@deftypefun int get_nprocs_conf (void) +The @code{get_nprocs_conf} function returns the number of processors the +operating system configured. + +This function is a GNU extension. +@end deftypefun + +@comment sys/sysinfo.h +@comment GNU +@deftypefun int get_nprocs (void) +The @code{get_nprocs} function returns the number of available processors. + +This function is a GNU extension. +@end deftypefun + @cindex load average Before starting more threads it should be checked whether the processors are not already overused. Unix systems calculate something called the |