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This is libgtop2.info, produced by makeinfo version 7.0.3 from
libgtop2.texi.
INFO-DIR-SECTION Libraries:
START-INFO-DIR-ENTRY
* LibGTop2: (libgtop2). Library to get system specific data
such as cpu and memory usage, active
processes
END-INFO-DIR-ENTRY
This is the LibGTop Reference Manual version 2.41.3 (last modified 27
November 2016).
Copyright 1999 Free Software Foundation, Inc.
Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.
Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided also
that the sections entitled “Copying” and “GNU General Public License”
are included exactly as in the original, and provided that the entire
resulting derived work is distributed under the terms of a permission
notice identical to this one.
Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions, except that this permission notice may be stated in a
translation approved by the Free Software Foundation.

File: libgtop2.info, Node: Top, Next: About, Prev: (dir), Up: (dir)
* Menu:
* About:: About LibGTop
* White Paper:: LibGTop White Paper
* Reference Manual:: LibGTop Reference Manual
— The Detailed Node Listing —
About LibGTop
* Availability:: Where to get LibGTop
* Supported Platforms:: Supported Platforms
* Mailing List:: Helping with LibGTop development
* Thanks:: People who contributed to LibGTop
LibGTop White Paper
* Introduction:: Introduction
* Overview:: Overview
Overview
* Interface Design:: Things that need to be considered
* Server Implementation:: The LibGTop "server"
LibGTop Reference Manual
* System Dependent:: System Dependent Functions.
* Common Functions:: Common Functions.
* Library Functions:: Library Functions.
System Dependent Functions
* glibtop_cpu:: CPU Usage.
* glibtop_mem:: Memory Usage.
* glibtop_swap:: Swap Usage.
* glibtop_uptime:: System Uptime.
* glibtop_loadavg:: Load Average.
* glibtop_proclist:: Process List.
* glibtop_proc_state:: Process State.
* glibtop_proc_uid:: Process UID and TTY Information.
* glibtop_proc_mem:: Process Memory Information.
* glibtop_proc_time:: Process Time Information.
* glibtop_proc_signal:: Process Signal Information.
* glibtop_proc_kernel:: Process Kernel Data Information.
* glibtop_proc_segment:: Process Segment Information.
* glibtop_proc_args:: Process Arguments.
* glibtop_proc_map:: Process Memory Maps.
* glibtop_netload:: Network Load.
* glibtop_ppp:: PPP Usage.
* glibtop_disk:: DISK Usage.
Common Functions
* glibtop_mountlist:: Mount List.
* glibtop_fsusage:: File System Usage.
Library Functions
* glibtop_init:: Server Initialization.
* glibtop_sysdeps:: Server Sysdeps.
* Library Parameters:: Library Parameters.

File: libgtop2.info, Node: About, Next: White Paper, Prev: Top, Up: Top
1 About LibGTop
***************
LibGTop is a library to get system specific data such as CPU and Memory
Usage and information about running Processes.
On Systems like Solaris or Digital Unix where you need special
privileges to get those data, it uses a setuid/setgid server to do so.
Even if LibGTop is a part of the GNOME desktop environment
(<http://www.gnome.org>), the main interface of LibGTop is totally
independent from any particular desktop environment, so you can also use
it as a standalone library in any piece of GPLed software.
* Menu:
* Availability:: Where to get LibGTop
* Supported Platforms:: Supported Platforms
* Mailing List:: Helping with LibGTop development
* Thanks:: People who contributed to LibGTop

File: libgtop2.info, Node: Availability, Next: Supported Platforms, Prev: About, Up: About
1.1 Availability
================
The master source of LibGTop is the GNOME CVS tree (see
<http://www.gnome.org> for details), but you can also get the latest
release tarballs from
<ftp://ftp.gnome.org/pub/GNOME/sources/libgtop/>
or any of its mirror sites.
The latest stable version of LibGTop is 1.0.12 which is also the one
that comes together with GNOME 1.0. It belongs to LIBGTOP_STABLE_1_0
branch in CVS. Actual development occurs in the libgtop-GNOME-2-0-port
which is currently versioned 1.90.0.

File: libgtop2.info, Node: Supported Platforms, Next: Mailing List, Prev: Availability, Up: About
1.2 Supported Platforms
=======================
The stable branch currently supports the following platforms:
• All versions of Linux
LibGTop was tested under Linux 2.0.x and 2.2.x on the ix86 and the
alpha, but it should also work without problems on SparcLinux or
Linux 2.4.x.
Note: Im speaking of the Linux kernel here, not the GNU/Linux
operating system.
• FreeBSD, NetBSD and OpenBSD
LibGTop was tested under FreeBSD 2.2.6 and 3.0, NetBSD 1.3.2 and
OpenBSD 2.4. Support for NetBSD 1.4 was added in LibGTop 1.0.2.
The platforms listed above are known to be stable and working.
However, if youre using the latest development version, you can use it
on the following platforms as well:
• BSD/OS
There is a port for BSD/OS (aka BSDI) 2.x and 3.x from Timur
Bakeyev which should also work with 4.x. This isnt tested very
well, but it should be working.
• Digital Unix
There is some basic support for Digital Unix (formerly DEC OSF/1)
V3.2C, but this may still be a bit unstable. Im currently working
on this port as time permits so it should be fully supported soon.
• Solaris
The Solaris port currently works on Solaris 7 and maybe also on
other releases. Thanks a lot to Drazen Kacar and everyone who
helped working on this port. They have really done excellent work
here and Im pretty sure that this port will be fully functional on
most Solaris versions in near future.

File: libgtop2.info, Node: Mailing List, Next: Thanks, Prev: Supported Platforms, Up: About
1.3 Mailing List
================
There is a <libgtop-devel-list@egroups.com> mailing list for people who
want to help with the development of LibGTop.
It is meant as a low-traffic, but high content-list where we can
discuss technical details such as adding new sysdeps ports etc.
Especially, Id like to see people with a deeper knowledge of
operating systems internals joining my list so we can discuss technical
details of the sysdeps code.
It is *not* for users that want to know how to compile LibGTop etc.
You can subscribe to this mailing list and view the mailing list
archives on the LibGTop Page at
<http://www.home-of-linux.org/gnome/libgtop>.

File: libgtop2.info, Node: Thanks, Prev: Mailing List, Up: About
1.4 Thanks
==========
At the place Id like to thank the following people who contributed to
LibGTop (listed in chronological order):
• Sebastian Wilhelmi who had the initial idea of LibGTop and helped
me a lot in the early beginning.
• Josh Sled for the initial FreeBSD port.
• Jeremy Lea for his BSD patches.
• Timur Bakeyev for the BSDI port.
• Drazen Kacar and the other people on the LibGTop development
mailing list for the Solaris port.
• Kevin Vandersloot for the effort to port to GNOME 2.0.
• All people sending me patches, having good ideas, ...
• Everyone I have forgotten in this list ...

File: libgtop2.info, Node: White Paper, Next: Reference Manual, Prev: About, Up: Top
2 LibGTop White Paper
*********************
* Menu:
* Introduction:: Introduction
* Overview:: Overview

File: libgtop2.info, Node: Introduction, Next: Overview, Prev: White Paper, Up: White Paper
2.1 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.
• BSD, for instance, doesnt have any other way to get those data
than reading directly from /dev/kmem and you need to be in the
kmem group to be able to read this.
• 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 youre not root).
• Linux has a very nice /proc filesystem, but reading and parsing
/proc is very slow and inefficient.
• Solaris is a bit better, but you still need to be in the sys
group or even root to get some data.
Because of this system utilities like ps, uptime or top often
are setgid kmem or setuid root. Usually, theyre also very specific to
the system theyre written for and not easily portable to other systems
without a lot of work.
This, of cause, becomes a problem for graphical tools like gtop -
making a GTK+ program setgid or even setuid would be a security hole as
big as you can drive the entire X11 source code through. For the GNOME
project, we also needed some kind of library which provides all the
required information in a portable since theres more than just one
single program that wants to use them - for instance gtop and the
multiload, cpumemusage and netload panel applets.

File: libgtop2.info, Node: Overview, Prev: Introduction, Up: White Paper
2.2 Overview
============
This section should give you a short overview on how LibGTop was
developed, which things needed to be considered and how it works.
* Menu:
* Interface Design:: Things that need to be considered
* Server Implementation:: The LibGTop "server"

File: libgtop2.info, Node: Interface Design, Next: Server Implementation, Prev: Overview, Up: Overview
2.2.1 Interface Design
----------------------
At the very beginning, it was necessary to collect all the data the
library part should provide and put them into some C structures. This
was not that easiy as it might sound since LibGTop should be portable to
any modern UNIX system with a common library part on all those systems,
but the data that should be returned vary from system to system. For
instance some systems support shared memory, but some others may not.
The header files where we define these C structures (which are
system-independent) are shared between client and server. This way we
can call the system dependent code directly where we do not need any
special privileges to do so.
All of those structures contain a flags member which is interpreted
as a bit mask and tells the caller of the library functions which of the
fields in the returned structure are valid and which are not.

File: libgtop2.info, Node: Server Implementation, Prev: Interface Design, Up: Overview
2.2.2 Server Implementation
---------------------------
The LibGTop “server” is a setgid/setuid binary which contains all the
system dependent code which needs special privileges. It is only build
if its required on the current system (for instance, the Linux kernel
provides all the required data via its /proc filesystem so we do not
need the server at all) and it only contains the “features” which need
privileges.
Whenever we do not need any privileges to get all the data for some
of the requested structures (here called “features”) the library calls
the sysdeps code directly rather than using the server.

File: libgtop2.info, Node: Reference Manual, Prev: White Paper, Up: Top
3 LibGTop Reference Manual
**************************
* Menu:
* System Dependent:: System Dependent Functions.
* Common Functions:: Common Functions.
* Library Functions:: Library Functions.

File: libgtop2.info, Node: System Dependent, Next: Common Functions, Prev: Reference Manual, Up: Reference Manual
3.1 System Dependent Functions
==============================
* Menu:
* glibtop_cpu:: CPU Usage.
* glibtop_mem:: Memory Usage.
* glibtop_swap:: Swap Usage.
* glibtop_uptime:: System Uptime.
* glibtop_loadavg:: Load Average.
* glibtop_proclist:: Process List.
* glibtop_proc_state:: Process State.
* glibtop_proc_uid:: Process UID and TTY Information.
* glibtop_proc_mem:: Process Memory Information.
* glibtop_proc_time:: Process Time Information.
* glibtop_proc_signal:: Process Signal Information.
* glibtop_proc_kernel:: Process Kernel Data Information.
* glibtop_proc_segment:: Process Segment Information.
* glibtop_proc_args:: Process Arguments.
* glibtop_proc_map:: Process Memory Maps.
* glibtop_netload:: Network Load.
* glibtop_ppp:: PPP Usage.
* glibtop_disk:: DISK Usage.

File: libgtop2.info, Node: glibtop_cpu, Next: glibtop_mem, Prev: System Dependent, Up: System Dependent
3.1.1 CPU Usage
---------------
Library function glibtop_get_cpu:
void glibtop_get_cpu (glibtop_cpu *buf);
void glibtop_get_cpu_l (glibtop *server, glibtop_cpu *buf);
Declaration of glibtop_cpu in <glibtop/cpu.h>:
typedef struct _glibtop_cpu glibtop_cpu;
struct _glibtop_cpu
{
guint64 flags,
total,
user,
nice,
sys,
idle,
iowait,
irq,
softirq,
frequency,
xcpu_total [GLIBTOP_NCPU],
xcpu_user [GLIBTOP_NCPU],
xcpu_nice [GLIBTOP_NCPU],
xcpu_sys [GLIBTOP_NCPU],
xcpu_idle [GLIBTOP_NCPU],
xcpu_iowait [GLIBTOP_NCPU],
xcpu_irq [GLIBTOP_NCPU],
xcpu_softirq [GLIBTOP_NCPU],
xcpu_flags;
};
All CPU units are measured in “jiffies” which are normally 1/100th of
a second (in which case frequency equals 100), but can also be in any
other unit. To get seconds, divide them by frequency.
total
Number of clock ticks since system boot.
user
Number of clock ticks the system spent in user mode.
nice
Number of clock ticks the system spent in user mode (nice).
sys
Number of clock ticks the system spent in system mode.
idle
Number of clock ticks the system spent in the idle task.
iowait
Number of clock ticks the system spent waiting for I/O to complete.
irq
Number of clock ticks the system spent servicing interrupts.
softirq
Number of clock ticks the system spent servicing softirqs.
frequency
Tick frequency (default is 100).
The xcpu_ values are for SMP systems - they are the same than
total, user, nice, sys, idle, iowait, irq and softirq
except that they are arrays of GLIBTOP_NCPU (defined in
<glibtop/cpu.h>) elements and contain one value for each CPU in the
system.
xcpu_flags
This is interpreted as a bit-field: on systems like Solaris, not
all CPUs need to be running all the time, so we set the
corresponding bit for each CPU that is currently running.
Please note that all of the cpu values are absolute values measured
in certain units (to get seconds, divide them by frequency) since
system boot. To get percentual values, you need to call glibtop_cpu,
save the result, wait some time and then call it again and divide the
differences of the two values by the time you have waited.

File: libgtop2.info, Node: glibtop_mem, Next: glibtop_swap, Prev: glibtop_cpu, Up: System Dependent
3.1.2 Memory Usage
------------------
Library function glibtop_get_mem:
void glibtop_get_mem (glibtop_mem *buf);
void glibtop_get_mem_l (glibtop *server, glibtop_mem *buf);
Declaration of glibtop_mem in <glibtop/mem.h>:
typedef struct _glibtop_mem glibtop_mem;
struct _glibtop_mem
{
guint64 flags,
total,
used,
free,
shared,
buffer,
cached,
user,
locked;
};
Unless explicitly stated otherwise, all memory units are in bytes.
total
Total physical memory.
used
Used memory size.
free
Free memory size.
shared
Shared memory size.
This are both segments that are mmap()ed with MAP_SHARED and
IPC Shared Memory segments.
buffer
Size of buffers.
cached
Size of cached memory.
user
Memory used from user processes.
This is normally total - free - shared - buffer - cached.
locked
Memory in locked segments.

File: libgtop2.info, Node: glibtop_swap, Next: glibtop_uptime, Prev: glibtop_mem, Up: System Dependent
3.1.3 Swap Usage
----------------
Library function glibtop_get_swap:
void glibtop_get_swap (glibtop_swap *buf);
void glibtop_get_swap_l (glibtop *server, glibtop_swap *buf);
Declaration of glibtop_swap in <glibtop/swap.h>:
typedef struct _glibtop_swap glibtop_swap;
struct _glibtop_swap
{
guint64 flags,
total,
used,
free,
pagein,
pageout;
};
The following units are in bytes.
total
Total swap space in the system.
used
Used swap space.
free
Free swap space.
You can use pagein and pageout to get some measure about how much
the system is swapping at the moment. Theyre increased each time a
page is swapped in or out, so you need to save this values, wait a
little bit, get them again and then compare the two results to find out
how much the system swapped in the meantime.
pagein
Total number of swap pages that have been brought in since system
boot
pageout
Total number of swap pages that have been brought out since system
boot

File: libgtop2.info, Node: glibtop_uptime, Next: glibtop_loadavg, Prev: glibtop_swap, Up: System Dependent
3.1.4 Uptime
------------
Library function glibtop_get_uptime:
void glibtop_get_uptime (glibtop_uptime *buf);
void glibtop_get_uptime_l (glibtop *server, glibtop_uptime *buf);
Declaration of glibtop_uptime in <glibtop/uptime.h>:
typedef struct _glibtop_uptime glibtop_uptime;
struct _glibtop_uptime
{
guint64 flags;
double uptime,
idletime;
guint64 boot_time;
};
When porting LibGTop to a new system, you only need to implement
uptime and idletime if theres a faster or better way to obtain them
as using glibtop_cpu for it. Look at sysdeps/freebsd/uptime.c for
an example on how to obtain them using glibtop_cpu.
uptime
Time in seconds since system boot.
idletime
Time in seconds the system spent in the idle task since system
boot.
The following one was from a request on the linux-kernel mailing
list; on a laptop with advanced power management glibtop_cpu.total may
not reflect the correct boot time of the system if the power was turned
off by means of APM in the meantime.
boot_time
Time of last system boot in seconds since the epoch.

File: libgtop2.info, Node: glibtop_loadavg, Next: glibtop_proclist, Prev: glibtop_uptime, Up: System Dependent
3.1.5 Load Average
------------------
Library function glibtop_get_loadavg:
void glibtop_get_loadavg (glibtop_loadavg *buf);
void glibtop_get_loadavg_l (glibtop *server, glibtop_loadavg *buf);
Declaration of glibtop_loadavg in <glibtop/loadavg.h>:
typedef struct _glibtop_loadavg glibtop_loadavg;
struct _glibtop_loadavg
{
guint64 flags;
double loadavg [3];
guint64 nr_running,
nr_tasks,
last_pid;
};
loadavg
Number of jobs running simultaneously averaged over 1, 5 and 15
minutes.
The following fields are Linux specific and deprecated. You dont
need to implement them when porting LibGTop to a new system as they may
be removed in a future version.
nr_running
Number of tasks currently running.
nr_tasks
Total number of tasks.
last_pid
Last PID.

File: libgtop2.info, Node: glibtop_proclist, Next: glibtop_proc_state, Prev: glibtop_loadavg, Up: System Dependent
3.1.6 Process List
------------------
Library function glibtop_get_proclist:
unsigned *
glibtop_get_proclist (glibtop_proclist *buf,
gint64 which, gint64 arg);
unsigned *
glibtop_get_proclist_l (glibtop *server, glibtop_proclist *buf,
gint64 which, gint64 arg);
Constants for the which argument:
#define GLIBTOP_KERN_PROC_ALL 0
#define GLIBTOP_KERN_PROC_PID 1
#define GLIBTOP_KERN_PROC_PGRP 2
#define GLIBTOP_KERN_PROC_SESSION 3
#define GLIBTOP_KERN_PROC_TTY 4
#define GLIBTOP_KERN_PROC_UID 5
#define GLIBTOP_KERN_PROC_RUID 6
#define GLIBTOP_KERN_PROC_MASK 15
#define GLIBTOP_EXCLUDE_IDLE 0x1000
#define GLIBTOP_EXCLUDE_SYSTEM 0x2000
#define GLIBTOP_EXCLUDE_NOTTY 0x4000
Declaration of glibtop_proclist in <glibtop/proclist.h>:
typedef struct _glibtop_proclist glibtop_proclist;
struct _glibtop_proclist
{
guint64 flags,
number,
total,
size;
};
This function returns a list of all or a selected subset of all
running processes. You can use the which and arg arguments to
specify which processes should be returned.
You can use the following values for the which argument:
GLIBTOP_KERN_PROC_ALL
Return information about all processes (the arg argument is
ignored).
GLIBTOP_KERN_PROC_PID
Return information about all process with the pid PID which is
passed in arg. You can use this to find out whether some process
still exists.
GLIBTOP_KERN_PROC_PGRP
Return all processes in process group PGRP which is passed in
arg.
GLIBTOP_KERN_PROC_SESSION
Return all processes in session SESSION which is passed in arg.
GLIBTOP_KERN_PROC_TTY
Return all processes which have the controlling tty TTY which is
passed in arg (TTY is interpreted as device number).
GLIBTOP_KERN_PROC_UID
Return all processes with effective uid UID which is passed in
arg.
GLIBTOP_KERN_PROC_RUID
Return all processes with real uid RUID which is passed in arg.
You can alter the list of returned processes by using a binary OR of
which and the following constants:
GLIBTOP_EXCLUDE_IDLE
Exclude idle processes.
GLIBTOP_EXCLUDE_SYSTEM
Exclude system processes.
GLIBTOP_EXCLUDE_NOTTY
Exclude processes without a controlling terminal.
The return value of glibtop_get_proclist is either NULL on error
or a unsigned * list of pids. Additionally, the following fields of
glibtop_proclist are set:
number
Number of entries in the returned list.
total
Total size of the returned list (this equals number * size).
size
Size of a single entry in the returned list (this equals sizeof
(unsigned)).
The returned list is allocated using g_malloc and must be freed
using g_free to avoid a memory leak.

File: libgtop2.info, Node: glibtop_proc_state, Next: glibtop_proc_uid, Prev: glibtop_proclist, Up: System Dependent
3.1.7 Process State
-------------------
Library function glibtop_get_proc_state:
void
glibtop_get_proc_state (glibtop_proc_state *buf, pid_t pid);
void
glibtop_get_proc_state_l (glibtop *server, glibtop_proc_state *buf,
pid_t pid);
Declaration of glibtop_proc_state in <glibtop/procstate.h>:
typedef struct _glibtop_proc_state glibtop_proc_state;
struct _glibtop_proc_state
{
guint64 flags;
char cmd[40];
char state;
int uid,
gid,
ruid,
rgid;
int has_cpu,
processor,
last_processor;
};
cmd
Basename of the executable file in the call to exec.
state
Process state (R = running, S = sleeping, D =
uninterruptible, Z = zombie, T = stopped, I = idle).
This was changed to an unsigned bitfield in LibGTop 1.1.x where
there are also some constants for it.
When porting LibGTop, please _try hard_ to implement the following
fields. For security reasons, it is *very important* that you *only*
set the flags bits for those fields if their *values are correct*.
uid
Effective UID of the process.
gid
Effective GID of the process.
ruid
Real UID of the process.
rgid
Read GID of the process.
The following fields are for SMP systems:
has_cpu
This is either 0 or 1 depending on whether the process currently
has a CPU or not.
processor
This is the processor id of the CPU this process is currently
running on (which can be used as index in the xcpu_ fields of
glibtop_cpu for instance; since zero is a valid processor id, you
must check has_cpu in this case to find out whether the process
really has a CPU).
last_processor
The is the processor id of the CPU the process was last running on.
GLIBTOP_PROCESS_RUNNING
The process is currently running.
GLIBTOP_PROCESS_INTERRUPTIBLE
The process is currently in an interruptible sleep.
GLIBTOP_PROCESS_UNINTERRUPTIBLE
The process is currently in uninterruptible sleep (the so-called
“disk sleep”).
GLIBTOP_PROCESS_ZOMBIE
The process is a zombie.
GLIBTOP_PROCESS_STOPPED
The process is currently stopped (received SIGSTOP or attached to
a debugger).
GLIBTOP_PROCESS_SWAPPING
The process is currently swapping.

File: libgtop2.info, Node: glibtop_proc_uid, Next: glibtop_proc_mem, Prev: glibtop_proc_state, Up: System Dependent
3.1.8 Process UID and TTY information
-------------------------------------
Library function glibtop_get_proc_uid:
void
glibtop_get_proc_uid (glibtop_proc_uid *buf, pid_t pid);
void
glibtop_get_proc_uid_l (glibtop *server, glibtop_proc_uid *buf,
pid_t pid);
Declaration of glibtop_proc_uid in <glibtop/procuid.h>:
typedef struct _glibtop_proc_uid glibtop_proc_uid;
struct _glibtop_proc_uid
{
guint64 flags;
int uid,
euid,
gid,
egid,
suid,
sgid,
fsuid,
fsgid,
pid,
ppid,
pgrp,
session,
tty,
tpgid,
priority,
nice,
ngroups,
groups [GLIBTOP_MAX_GROUPS];
};
uid
User ID
euid
Effective User ID
gid
Group ID
egid
Effective Group ID
pid
Process ID
ppid
PID of parent process
pgrp
Process group ID
session
Session ID
tty
Full device number of controlling terminal
tpgid
Terminal process group ID
priority
Kernel scheduling priority.
nice
Standard unix nice level of process.
ngroups
Number of additional process groups.
groups
Array of additional process groups
(GLIBTOP_MAX_GROUPS is defined in <glibtop/procuid.h>).

File: libgtop2.info, Node: glibtop_proc_mem, Next: glibtop_proc_time, Prev: glibtop_proc_uid, Up: System Dependent
3.1.9 Process Memory information
--------------------------------
Library function glibtop_get_proc_mem:
void
glibtop_get_proc_mem (glibtop_proc_mem *buf, pid_t pid);
void
glibtop_get_proc_mem_l (glibtop *server, glibtop_proc_mem *buf,
pid_t pid);
Declaration of glibtop_proc_mem in <glibtop/procmem.h>:
typedef struct _glibtop_proc_mem glibtop_proc_mem;
struct _glibtop_proc_mem
{
guint64 flags,
size,
vsize,
resident,
share,
rss,
rss_rlim;
};
size
Total number of pages of memory.
vsize
Number of pages of virtual memory.
resident
Number of residnet set (non-swapped) pages.
share
Number of pages of shared (mmap\d) memory.
rss
Number of pages the process has in real memory, minus 3 for
administrative purposes.
This is just the pages which count towards text, data, or stack
space. This does not include pages which have not been
demand-loaded in, or which are swapped out.
rss_rlim
Current limit in bytes on the rss of the process (usually
2,147,483,647).
The description above is taken from the manual page of the /proc
filesystem under Linux and is a little bit confusing, so I make this
clear here.
*A word for people porting LibGTop to other systems:* Every operating
system has its own idea about the memory usage of a process and also
system utilities like ps show different things on different systems.
Nevertheless, we should try to make LibGTop as system independent as
possible, so I give you some hints here how glibtop_get_proc_mem
should work.
• When you use mmap with either MAP_SHARED or MAP_PRIVATE, this
should only affect the vsize of the process and none of its
size, resident, shared and rss sizes.
• As soon as you read some of the mmap()ed pages, they will be
demand- oaded and thus count towards the size of the process.
Also - we assume there is enough free memory - they are resident in
memory until they get stolen or swapped out and thus increase the
resident and rss sizes of the process.
• If the process has used MAP_SHARED and another process attaches
the same file also MAP_SHARED, some of the pages are shared with
this process and thus increase the shared sizes of both
processes.
• If the process has used MAP_PRIVATE and writes to the mmap()ed
pages, the only difference to reading from them is that they get
dirty and cannot be stolen any longer but will get swapped out.
• When memory gets rare, clean pages are normally stolen, which
decreases the size, resident, shared and rss sizes of the
process.
• When dirty pages are swapped out, this will not decrease the size
of the process but only its resident and rss sizes (dirty pages
cannot be shared).
• The vsize of a process can _only_ be changed by the process
itself when it requests or frees memory but _never_ due to swapping
activity of the system.
• If the shared size changes, this _only_ means that the number of
pages that are currently shared with other processes has changed;
if this happens, this will _never_ affect any of the other sizes of
the process.
The hints above describe how it works under Linux - but we should try
to make glibtop_get_proc_mem show the same behavior under every other
system.

File: libgtop2.info, Node: glibtop_proc_time, Next: glibtop_proc_signal, Prev: glibtop_proc_mem, Up: System Dependent
3.1.10 Process Time information
-------------------------------
Library function glibtop_get_proc_time:
void
glibtop_get_proc_time (glibtop_proc_time *buf, pid_t pid);
void
glibtop_get_proc_time_l (glibtop *server, glibtop_proc_time *buf,
pid_t pid);
Declaration of glibtop_proc_time in <glibtop/proctime.h>:
typedef struct _glibtop_proc_time glibtop_proc_time;
struct _glibtop_proc_time
{
guint64 flags,
start_time,
rtime,
utime,
stime,
cutime,
cstime,
timeout,
it_real_value,
frequency,
xcpu_utime [GLIBTOP_NCPU],
xcpu_stime [GLIBTOP_NCPU],
xcpu_flags;
};
start_time
Start time of process in seconds since the epoch
rtime
Real time accumulated by process (should be utime + stime)
utime
User-mode CPU time accumulated by process
stime
Kernel-mode CPU time accumulated by process
cutime
Cumulative utime of process and reaped children
cstime
Cumulative stime of process and reaped children
timeout
The time (in jiffies) of the processs next timeout
it_real_value
The time (in jiffies) before the next SIGALRM is sent to the
process due to an interval timer.
frequency
Tick frequency
xcpu_utime
SMP user-mode CPU time accumulated by process
xcpu_stime
SMP kernel-mode CPU time accumulated by process
Please note that under Linux, start_time value may be strange.
Linux kernel defines INITIAL_JIFFIES which implies a time shift.
Because INITIAL_JIFFIES is not user-space defined, we cannot use it to
compute accurate start_time. On Linux2.6, INITIAL_JIFFIES is 300 so
start_time is always 3s different from real start time of the given
process. You may also get shift results if your system clock is not
synchronised with your hardware clock. See man hwclock.

File: libgtop2.info, Node: glibtop_proc_signal, Next: glibtop_proc_kernel, Prev: glibtop_proc_time, Up: System Dependent
3.1.11 Process Signal information
---------------------------------
Library function glibtop_get_proc_signal:
void
glibtop_get_proc_signal (glibtop_proc_signal *buf, pid_t pid);
void
glibtop_get_proc_signal_l (glibtop *server, glibtop_proc_signal *buf,
pid_t pid);
Declaration of glibtop_proc_signal in <glibtop/procsignal.h>:
typedef struct _glibtop_proc_signal glibtop_proc_signal;
struct _glibtop_proc_signal
{
guint64 flags,
signal [2],
blocked [2],
sigignore [2],
sigcatch [2];
};
signal
Mask of pending signals
blocked
Mask of blocked signals
sigignore
Mask of ignored signals
sigcatch
Mask of caught signals
All signal masks are interpreted as bit mask; it is an array of two
guint64s so we can save 128 signals there.

File: libgtop2.info, Node: glibtop_proc_kernel, Next: glibtop_proc_segment, Prev: glibtop_proc_signal, Up: System Dependent
3.1.12 Process Kernel Data information
--------------------------------------
Library function glibtop_get_proc_kernel:
void
glibtop_get_proc_kernel (glibtop_proc_kernel *buf, pid_t pid);
void
glibtop_get_proc_kernel_l (glibtop *server, glibtop_proc_kernel *buf,
pid_t pid);
Declaration of glibtop_proc_kernel in <glibtop/prockernel.h>:
typedef struct _glibtop_proc_kernel glibtop_proc_kernel;
struct _glibtop_proc_kernel
{
guint64 flags;
guint64 k_flags,
min_flt,
maj_flt,
cmin_flt,
cmaj_flt,
kstk_esp,
kstk_eip,
nwchan;
char wchan [40];
};
k_flags
Kernel flags of the process. See the constants defined below.
min_flt
The number of minor faults the process has made, those which have
not required loading a memory page from disk.
maj_flt
The number of major faults the process has made, those which have
required loading a memory page from disk.
cmin_flt
The number of minor faults that the process and its children have
made.
cmaj_flt
The number of major faults that the process and its children have
made.
kstk_esp
The current value of esp (32-bit stack pointer), as found in the
kernel stack page for the process.
kstk_eip
The current eip (32-bit instruction pointer).
nwchan
This is the "channel" in which the process is waiting. This is the
address of a system call, and can be looked up in a namelist if you
need a textual name. (If you have an up-to-date /etc/psdatabase,
then try ps -l to see the WCHAN field in action).
wchan
This is the textual name of the nwchan field.
There are some constants for the k_flags field:
#define GLIBTOP_KFLAGS_STARTING 1
#define GLIBTOP_KFLAGS_EXITING 2
#define GLIBTOP_KFLAGS_PTRACED 4
#define GLIBTOP_KFLAGS_TRACESYS 8
#define GLIBTOP_KFLAGS_FORKNOEXEC 16
#define GLIBTOP_KFLAGS_SUPERPRIV 32
#define GLIBTOP_KFLAGS_DUMPEDCORE 64
#define GLIBTOP_KFLAGS_SIGNALED 128
GLIBTOP_KFLAGS_STARTING
Process is being created.
GLIBTOP_KFLAGS_EXITING
Process is exiting.
GLIBTOP_KFLAGS_PTRACED
Process is being traced (via ptrace ()).
GLIBTOP_KFLAGS_TRACESYS
Process is tracing system calls.
GLIBTOP_KFLAGS_FORKNOEXEC
Process fork()ed, but didnt exec() yet.
GLIBTOP_KFLAGS_SUPERPRIV
Process used super-user privileges.
GLIBTOP_KFLAGS_DUMPEDCORE
Process dumped core.
GLIBTOP_KFLAGS_SIGNALED
Process was killed by a signal.

File: libgtop2.info, Node: glibtop_proc_segment, Next: glibtop_proc_args, Prev: glibtop_proc_kernel, Up: System Dependent
3.1.13 Process Segment information
----------------------------------
Library function glibtop_get_proc_segment:
void
glibtop_get_proc_segment (glibtop_proc_segment *buf, pid_t pid);
void
glibtop_get_proc_segment_l (glibtop *server, glibtop_proc_segment *buf,
pid_t pid);
Declaration of glibtop_proc_segment in <glibtop/procsegment.h>:
typedef struct _glibtop_proc_segment glibtop_proc_segment;
struct _glibtop_proc_segment
{
guint64 flags,
text_rss,
shlib_rss,
data_rss,
stack_rss,
dirty_size,
start_code,
end_code,
start_stack;
};
text_rss
Text resident set size
shlib_rss
Shared-Lib resident set size
data_rss
Data resident set size
stack_rss
Stack resident set size
dirty_size
Total size of dirty pages
start_code
Address of beginning of code segment
end_code
Address of end of code segment
start_stack
Address of the bottom of stack segmen

File: libgtop2.info, Node: glibtop_proc_args, Next: glibtop_proc_map, Prev: glibtop_proc_segment, Up: System Dependent
3.1.14 Process Arguments
------------------------
Library function glibtop_get_proc_args:
char *
glibtop_get_proc_args(glibtop_proc_args *buf, pid_t pid,
unsigned max_len);
char *
glibtop_get_proc_args_l (glibtop *server, glibtop_proc_args *buf,
pid_t pid, unsigned max_len);
Declaration of glibtop_proc_args in <glibtop/procargs.h>:
typedef struct _glibtop_proc_args glibtop_proc_args;
struct _glibtop_proc_args
{
guint64 flags,
size;
};
Returns a string with all command line arguments of process pid (up
to max_len characters, use zero to get all arguments).
The command line arguments in the returned string are separated by
zero bytes; the lenght of this string is returned in the size field.
Remember to g_free the returned string to avoid a memory leak.
*New functions*
char **
glibtop_get_proc_argv(glibtop_proc_args *buf, pid_t pid,
unsigned max_len);
char **
glibtop_get_proc_argv_l (glibtop *server, glibtop_proc_args *buf,
pid_t pid, unsigned max_len);
Returns a NULL-terminated array of strings with all arguments of
process pid (up to max_len characters, use zero to get all
arguments). glibtop_get_proc_argv() and glibtop_get_proc_argv_l()
are wrappers to glibtop_get_proc_args() and
glibtop_get_proc_args_l() that return process arguments like the C
argv.
Remember to g_strfreev the returned array to avoid a memory leak.

File: libgtop2.info, Node: glibtop_proc_map, Next: glibtop_netload, Prev: glibtop_proc_args, Up: System Dependent
3.1.15 Process Memory Maps
--------------------------
Library function glibtop_get_proc_map:
glibtop_map_entry *
glibtop_get_proc_map (glibtop_proc_map *buf, pid_t pid);
glibtop_map_entry *
glibtop_get_proc_map_l (glibtop *server, glibtop_proc_map *buf,
pid_t pid);
Declaration of glibtop_proc_map in <glibtop/procmap.h>:
typedef struct _glibtop_proc_map glibtop_proc_map;
struct _glibtop_proc_map
{
guint64 flags,
number,
total,
size;
};
Returns a glibtop_map_entry * list (which needs to be freed with
g_free) of memory maps of process pid.
number
Number of entries in the returned list.
total
Total size of the returned list (this equals number * size).
size
Size of a single entry in the returned list (this equals sizeof
(glibtop_map_entry)).
typedef struct _glibtop_map_entry glibtop_map_entry;
struct _glibtop_map_entry
{
guint64 flags, start, end, offset, perm, inode, device;
char filename [GLIBTOP_MAP_FILENAME_LEN+1];
};
The flags member is a bit field and specifies which of the other
fields are valid:
#define GLIBTOP_MAP_ENTRY_START 0
#define GLIBTOP_MAP_ENTRY_END 1
#define GLIBTOP_MAP_ENTRY_OFFSET 2
#define GLIBTOP_MAP_ENTRY_PERM 3
#define GLIBTOP_MAP_ENTRY_INODE 4
#define GLIBTOP_MAP_ENTRY_DEVICE 5
#define GLIBTOP_MAP_ENTRY_FILENAME 6
Constants for the perm member:
#define GLIBTOP_MAP_PERM_READ 1
#define GLIBTOP_MAP_PERM_WRITE 2
#define GLIBTOP_MAP_PERM_EXECUTE 4
#define GLIBTOP_MAP_PERM_SHARED 8
#define GLIBTOP_MAP_PERM_PRIVATE 16

File: libgtop2.info, Node: glibtop_netload, Next: glibtop_ppp, Prev: glibtop_proc_map, Up: System Dependent
3.1.16 Network Load
-------------------
Library function glibtop_get_netload:
void
glibtop_get_netload (glibtop_netload *buf, const char *interface);
void
glibtop_get_netload_l (glibtop *server, glibtop_netload *buf,
const char *interface);
Declaration of glibtop_netload in <glibtop/netload.h>:
typedef struct _glibtop_netload glibtop_netload;
struct _glibtop_netload
{
guint64 flags,
if_flags,
mtu,
subnet,
address,
packets_in,
packets_out,
packets_total,
bytes_in,
bytes_out,
bytes_total,
errors_in,
errors_out,
errors_total,
collisions;
};
Returns network statistics for interface interface (which is the
same than in ifconfig).
if_flags
Interface flags. See the contants defined below.
mtu
Maximum Transfer Unit (MTU)
subnet
Subnet Address
address
Interface Address
packets_in
Total number of incoming packets
packets_out
Total number of outgoing packets
packets_total
Total number of packets
bytes_in
Total number of incoming bytes
bytes_out
Total number of outgoing bytes
bytes_total
Total number of bytes
errors_in
Total number of errors in incoming direction
errors_out
Total number of errors in outgoing direction
errors_total
Total number of errors
collisions
Total number of collisions
Please note that not all operating systems distinguish between
incoming/outgoing bytes/packets/errors - in this case only the _total
fields are valid. Otherwise, theyre just _in plus _out.
Constants for if_flags:
enum {
GLIBTOP_IF_FLAGS_UP = 1,
GLIBTOP_IF_FLAGS_BROADCAST,
GLIBTOP_IF_FLAGS_DEBUG,
GLIBTOP_IF_FLAGS_LOOPBACK,
GLIBTOP_IF_FLAGS_POINTOPOINT,
GLIBTOP_IF_FLAGS_RUNNING,
GLIBTOP_IF_FLAGS_NOARP,
GLIBTOP_IF_FLAGS_PROMISC,
GLIBTOP_IF_FLAGS_ALLMULTI,
GLIBTOP_IF_FLAGS_OACTIVE,
GLIBTOP_IF_FLAGS_SIMPLEX,
GLIBTOP_IF_FLAGS_LINK0,
GLIBTOP_IF_FLAGS_LINK1,
GLIBTOP_IF_FLAGS_LINK2,
GLIBTOP_IF_FLAGS_ALTPHYS,
GLIBTOP_IF_FLAGS_MULTICAST
};

File: libgtop2.info, Node: glibtop_ppp, Next: glibtop_disk, Prev: glibtop_netload, Up: System Dependent
3.1.17 PPP Statistics
---------------------
Library function glibtop_get_ppp:
void
glibtop_get_ppp_l (glibtop *server, glibtop_ppp *buf,
unsigned short device);
void
glibtop_get_ppp (glibtop_ppp *buf, unsigned short device);
Declaration of glibtop_ppp in <glibtop/ppp.h>:
typedef struct _glibtop_ppp glibtop_ppp;
struct _glibtop_ppp
{
guint64 flags,
state,
bytes_in,
bytes_out;
};
bytes_in
Number of input bytes
bytes_out
Number of output bytes
There are some constants for state:
enum {
GLIBTOP_PPP_STATE_UNKNOWN = 0,
GLIBTOP_PPP_STATE_HANGUP,
GLIBTOP_PPP_STATE_ONLINE
};
GLIBTOP_PPP_STATE_UNKNOWN
LibGTop was unable to determine the current ppp state.
GLIBTOP_PPP_STATE_HANGUP
Were currently offline.
GLIBTOP_PPP_STATE_ONLINE
Were currently online.

File: libgtop2.info, Node: glibtop_disk, Prev: glibtop_ppp, Up: System Dependent
3.1.18 DISK Usage
-----------------
Library function glibtop_get_disk:
void glibtop_get_disk (glibtop_disk *buf);
void glibtop_get_disk_l (glibtop *server, glibtop_disk *buf);
Declaration of glibtop_disk in <glibtop/disk.h>:
typedef struct _glibtop_disk glibtop_disk;
struct _glibtop_disk
{
xdisk_sectors_read [GLIBTOP_NDISK],
xdisk_time_read [GLIBTOP_NDISK],
xdisk_sectors_write [GLIBTOP_NDISK],
xdisk_time_write [GLIBTOP_NDISK],
};
All DISK reads and writes are measured by “sectors” which are
normally 512 bytes each. All disk time are measured in milliseconds
which is 1/1000th of a second.
xdisk_sectors_read
Number of sectors read since system boot.
xdisk_time_read
Number of milliseconds spent reading since system boot.
xdisk_sectors_write
Number of sectors written since system boot.
xdisk_time_write
Number of milliseconds spent writing since system boot.
The xdisk_ are values from arrays of GLIBTOP_NDISK (defined in
<glibtop/disk.h>) elements and contain one value for each DISK in the
system.
Please note that all of the disk values are absolute values measured
in certain units since system boot. To get bandwidth values (bytes/s),
you need to call glibtop_disk, save the result, wait some time and
then call it again and divide the differences of the two values by the
time spent reading or writing.

File: libgtop2.info, Node: Common Functions, Next: Library Functions, Prev: System Dependent, Up: Reference Manual
3.2 Common Functions
====================
This are functions which a common implementation for all systems; we
never use the server for them.
The file system code is taken from GNU Fileutils.
* Menu:
* glibtop_mountlist:: Mount List.
* glibtop_fsusage:: File System Usage.

File: libgtop2.info, Node: glibtop_mountlist, Next: glibtop_fsusage, Prev: Common Functions, Up: Common Functions
3.2.1 Mount List
----------------
Library function glibtop_get_mountlist:
glibtop_mountentry *
glibtop_get_mountlist_l (glibtop *server, glibtop_mountlist *buf,
int all_fs);
glibtop_mountentry *
glibtop_get_mountlist (glibtop_mountlist *buf, int all_fs);
The all_fs parameter specifies whether information about all
filesystems should be returned; this will include filesystem types like
autofs and procfs. You should not use this in disk usage programs,
but it can be useful to get a list of all currently mounted filesystems.
Declaration of glibtop_proc_map in <glibtop/procmap.h>:
typedef struct _glibtop_mountlist glibtop_mountlist;
struct _glibtop_mountlist
{
guint64 flags,
number,
total,
size;
};
Returns a glibtop_mountentry * list (which needs to be freed with
g_free) of mounted filesystems.
number
Number of entries in the returned list.
total
Total size of the returned list (this equals number * size).
size
Size of a single entry in the returned list (this equals sizeof
(glibtop_mountentry)).
typedef struct _glibtop_mountentry glibtop_mountentry;
struct _glibtop_mountentry
{
guint64 dev;
char devname [GLIBTOP_MOUNTENTRY_LEN+1];
char mountdir [GLIBTOP_MOUNTENTRY_LEN+1];
char type [GLIBTOP_MOUNTENTRY_LEN+1];
};
GLIBTOP_MOUNTENTRY_LEN is defined in <glibtop.h>.
devname
Full pathname (such as /dev/sdb1 for instance) to the mounted
device.
mountdir
Full pathname of the mountpoint (such as /usr/local for
instance).
type
Filesystem type as a textual string (such as ext2fs).

File: libgtop2.info, Node: glibtop_fsusage, Prev: glibtop_mountlist, Up: Common Functions
3.2.2 File System Usage
-----------------------
Library function glibtop_get_fsusage:
void
glibtop_get_fsusage_l (glibtop *server, glibtop_fsusage *buf,
const char *mount_dir);
void
glibtop_get_fsusage (glibtop_fsusage *buf, const char *mount_dir);
Declaration of glibtop_fsusage in <glibtop/fsusage.h>:
typedef struct _glibtop_fsusage glibtop_fsusage;
struct _glibtop_fsusage
{
guint64 flags,
blocks,
bfree,
bavail,
files,
ffree;
guint32 block_size;
guint64 read,
write;
};
blocks
Total blocks in the filesystem.
bfree
Free blocks available to the superuser.
bavail
Free blocks available to ordinary users.
files
Total file nodes.
ffree
Free file nodes.
block_size
Block size in bytes.
read
Total blocks read.
write
Total blocks written.

File: libgtop2.info, Node: Library Functions, Prev: Common Functions, Up: Reference Manual
3.3 Library Functions
=====================
This are general library functions which can be used to get information
about the library and to control its behavior.
* Menu:
* glibtop_init:: Server Initialization.
* glibtop_sysdeps:: Server Sysdeps.
* Library Parameters:: Library Parameters.

File: libgtop2.info, Node: glibtop_init, Next: glibtop_sysdeps, Prev: Library Functions, Up: Library Functions
3.3.1 Server Initialization
---------------------------
You do not need to worry about the glibtop * server structure if you
dont need - the library exports a glibtop_global_server which you can
use everywhere a glibtop * is expected.
Most of the library and all of the sysdeps function also have an
alias (which is the function name without the _l, _s or _r suffix)
which dont take a glibtop * as argument but uses the
glibtop_global_server instead.
extern glibtop *glibtop_global_server;
Library function glibtop_init:
glibtop *
glibtop_init_r (glibtop **server_ptr, unsigned long features,
unsigned flags);
void
glibtop_init (void);
This function initializes a LibGTop server. It is automatically
called when you use any of the LibGTop functions and will use the global
server in this case.
However, its appreciated to call glibtop_init during the
initialization of your application.
You can for instance use
glibtop_init ();
which is equivalent to
glibtop_init_r (&glibtop_global_server, 0, 0);
Please note that the server_ptr argument is a pointer to a pointer
(and thus is of type glibtop **).
To control what glibtop_init should actually do, you can use the
features and flags arguments.
The features argument is a bit-mask (interpreted in the same way
than sysdeps.features) and tells the library which features youre
interested in. The library will only start the server if this is
required for any of those features.
You can use the following constants for the flags parameter to
control the behavior of the library:
GLIBTOP_INIT_NO_INIT
Tells the library to do nothing. If the value pointed to by the
server_ptr argument is NULL, it will set it to the
glibtop_global_server and then return.
GLIBTOP_INIT_NO_OPEN
Do the initialization, but do not start the server.
To modify the way the features are interpretet, you can use the
following constants for flags (as a bit mask):
GLIBTOP_FEATURES_NO_SERVER
Never use the server, always call the sysdeps code directly. If
you require any privileges to get them and you dont have those
privileges, the this will obviously not work and the library will
fail to return some or all of the requested values.
GLIBTOP_FEATURES_EXCEPT
Inverts the matching of the features parameter, i.e. if you use
this flag this means that features are all the features you are
_not_ interested in. Might be useful to say something like "I want
everything but ppp".

File: libgtop2.info, Node: glibtop_sysdeps, Next: Library Parameters, Prev: glibtop_init, Up: Library Functions
3.3.2 Server Sysdeps
--------------------
Library function glibtop_get_sysdeps:
void
glibtop_get_sysdeps_r (glibtop *server, glibtop_sysdeps *buf);
void
glibtop_get_sysdeps (glibtop_sysdeps *buf);
Declaration of glibtop_sysdeps in <glibtop/sysdeps.h>:
typedef struct _glibtop_sysdeps glibtop_sysdeps;
struct _glibtop_sysdeps
{
guint64 flags,
features,
pointer_size,
cpu,
mem,
swap,
uptime,
loadavg,
shm_limits,
msg_limits,
sem_limits,
proclist,
proc_state,
proc_uid,
proc_mem,
proc_time,
proc_signal,
proc_kernel,
proc_segment,
proc_args,
proc_map,
mountlist,
fsusage,
netload,
ppp;
};
features
This is a bit field (the so-called “server features”) stating for
which features we need to use the server.
pointer_size
This was added in LibGTop 1.1.0 and tells you the number of bits a
void* has in the server (this may be different from the size on
the client machine if were talking over the daemon to a remove
machine).
The following constants from <glibtop/sysdeps.h> serve as
bit-indices for the features field:
#define GLIBTOP_SYSDEPS_CPU 0
#define GLIBTOP_SYSDEPS_MEM 1
#define GLIBTOP_SYSDEPS_SWAP 2
#define GLIBTOP_SYSDEPS_UPTIME 3
#define GLIBTOP_SYSDEPS_LOADAVG 4
#define GLIBTOP_SYSDEPS_SHM_LIMITS 5
#define GLIBTOP_SYSDEPS_MSG_LIMITS 6
#define GLIBTOP_SYSDEPS_SEM_LIMITS 7
#define GLIBTOP_SYSDEPS_PROCLIST 8
#define GLIBTOP_SYSDEPS_PROC_STATE 9
#define GLIBTOP_SYSDEPS_PROC_UID 10
#define GLIBTOP_SYSDEPS_PROC_MEM 11
#define GLIBTOP_SYSDEPS_PROC_TIME 12
#define GLIBTOP_SYSDEPS_PROC_SIGNAL 13
#define GLIBTOP_SYSDEPS_PROC_KERNEL 14
#define GLIBTOP_SYSDEPS_PROC_SEGMENT 15
#define GLIBTOP_SYSDEPS_PROC_ARGS 16
#define GLIBTOP_SYSDEPS_PROC_MAP 17
#define GLIBTOP_SYSDEPS_MOUNTLIST 18
#define GLIBTOP_SYSDEPS_FSUSAGE 19
#define GLIBTOP_SYSDEPS_NETLOAD 20
#define GLIBTOP_SYSDEPS_PPP 21

File: libgtop2.info, Node: Library Parameters, Prev: glibtop_sysdeps, Up: Library Functions
3.3.3 Library Parameters
------------------------
Library function glibtop_get_parameter:
size_t
glibtop_get_parameter_l (glibtop *server, const unsigned parameter,
void *data_ptr, size_t data_size);
size_t
glibtop_get_parameter (const unsigned parameter, void *data_ptr,
size_t data_size);
This function is used to retrieve a library parameter (see below for
a more detailed description). It returns the size of the retrieved
parameter on success, zero on failure or minus the actual size of the
parameter if data_size was too small.
You may call this function with data_ptr set to NULL to get the
actual size of a parameter (as a negative value).
parameter
The parameter you want to retrieve (see below for constants).
data_ptr
Pointer to a place where the parameter should be stored.
data_size
Maximum size of the parameter.
Library function glibtop_set_parameter:
void
glibtop_set_parameter_l (glibtop *server, const unsigned parameter,
const void *data_ptr, size_t data_size);
void
glibtop_set_parameter (const unsigned parameter, const void *data_ptr,
size_t data_size);
This function is used to modify a library parameter. Please not that
you may not set all parameters since some of them are read-only.
parameter
The parameter you want to modify (see below for constants).
data_ptr
Pointer to the value which should be set.
data_size
Size of the new value. For fixed-size parameters, this must match
the exact size of the parameter or youll get an error.
The following parameters are defined in <glibtop/parameter.h>:
GLIBTOP_PARAM_FEATURES
This is a read-only unsigned long representing the features
field of glibtop_sysdeps.
GLIBTOP_PARAM_REQUIRED
This is a glibtop_sysdeps structure specifying which features the
client requires the library return. If it fails to get any of
them, youll get an error.
GLIBTOP_PARAM_ERROR_METHOD
This is an unsigned telling the library what to do if it fails to
get any of the features that are marked as required via the
GLIBTOP_PARAM_REQUIRED parameter (see below for constants).
You can use the following constants for GLIBTOP_PARAM_ERROR_METHOD
(defined in <glibtop/open.h>):
GLIBTOP_ERROR_METHOD_IGNORE
Ignore the error condition.
GLIBTOP_ERROR_METHOD_WARN_ONCE
Warn once about the absense of some of the required features, then
modify GLIBTOP_PARAM_REQUIRED so that the missing ones are no
longer required. This is the prefered value for applications since
itll only print out the warning message once and not each time the
library tries to get one of those features.
GLIBTOP_ERROR_METHOD_WARN
Warn each time the library fails to get some of the required
features.
GLIBTOP_ERROR_METHOD_ABORT
Abort if the library fails to get some of the required features.
This should not be used by applications.

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Node: Top1216
Node: About3413
Node: Availability4291
Node: Supported Platforms4919
Node: Mailing List6550
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Node: White Paper8052
Node: Introduction8285
Node: Overview10070
Node: Interface Design10437
Node: Server Implementation11468
Node: Reference Manual12203
Node: System Dependent12507
Node: glibtop_cpu13626
Node: glibtop_mem16369
Node: glibtop_swap17587
Node: glibtop_uptime18861
Node: glibtop_loadavg20210
Node: glibtop_proclist21248
Node: glibtop_proc_state24599
Node: glibtop_proc_uid27293
Node: glibtop_proc_mem28941
Node: glibtop_proc_time32810
Node: glibtop_proc_signal35056
Node: glibtop_proc_kernel36135
Node: glibtop_proc_segment39138
Node: glibtop_proc_args40420
Node: glibtop_proc_map42224
Node: glibtop_netload44253
Node: glibtop_ppp46855
Node: glibtop_disk47974
Node: Common Functions49564
Node: glibtop_mountlist49989
Node: glibtop_fsusage51989
Node: Library Functions53126
Node: glibtop_init53553
Node: glibtop_sysdeps56430
Node: Library Parameters59079

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