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Diffstat (limited to 'doc')
-rw-r--r-- | doc/ChangeLog | 2 | ||||
-rw-r--r-- | doc/white-paper.texi | 41 |
2 files changed, 43 insertions, 0 deletions
diff --git a/doc/ChangeLog b/doc/ChangeLog index 67c2d6ad..75a7a356 100644 --- a/doc/ChangeLog +++ b/doc/ChangeLog @@ -1,5 +1,7 @@ 1999-05-16 Martin Baulig <martin@home-of-linux.org> + * white-paper.texi: Initial version of the LibGTop White Paper. + * Makefile.am: Create `auto-macros.texi' from `auto-macros.texi.in' which will contain some `@set' commands for the LibGTop version etc. diff --git a/doc/white-paper.texi b/doc/white-paper.texi new file mode 100644 index 00000000..c625a738 --- /dev/null +++ b/doc/white-paper.texi @@ -0,0 +1,41 @@ +@node White Paper, Reference Manual, About, Top +@chapter LibGTop White Paper + +@menu +* Introduction:: +@end menu + +@node Introduction, , White Paper, White Paper +@section Introduction + +Many modern UNIX systems like Solaris, BSD or Digitial Unix only allow +priviledged processes to read information like CPU and Memory Usage or +information about running processes. + +@itemize @bullet +@item +BSD, for instance, doesn't have any other way to get those data than reading +directly from @file{/dev/kmem} and you need to be in the @code{kmem} group to +be able to read this. + +@item +Other systems, like Digital Unix, allow all users to get things like CPU and +Memory statistics, but only root may read information about any process other +than the current one (you may not even get information about your own processes +if you're not root). + +@item +Linux has a very nice @file{/proc} filesystem, but reading and parsing +@file{/proc} is very slow and inefficient. + +@item +Solaris is a bit better, but you still need to be in the @code{sys} group or +even root to get some data. +@end itemize + +Because of this system utilities like @code{ps}, @code{uptime} or @code{top} +often are setgid kmem or setuid root. Usually, they're also very specific to +the system they're written for and not easily portable to other systems without +a lot of work. + + |