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Consider the Unix command sequence ps aux | grep -iv apache2 | wc -l This command will output the total number of apache2 processes running.
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geom(8) [freebsd man page]

GEOM(8) 						    BSD System Manager's Manual 						   GEOM(8)

NAME
geom -- universal control utility for GEOM classes SYNOPSIS
geom class help geom class list [-a] [name ...] geom class status [-ags] [name ...] geom class load [-v] geom class unload [-v] DESCRIPTION
The geom utility is used to control various GEOM classes. A class has to be aware of geom(8) communication methods, but there are also some standard commands which can be used for existing geom(8) unaware classes. Here is the list of standard commands: help List all available commands for the given class. list Print detailed information (within the given class) about all geoms (if no additional arguments were specified) or the given geoms. This command is only available if the given class exists in the kernel. Additional options include: -a Print information for geoms without providers. status Print general information (within the given class) about all geoms (if no additional arguments were specified) or the given geoms. This command is only available if the given class exists in the kernel. Additional options include: -a When used with -g, print status for geoms without providers. -g Report statuses for geoms instead of providers. -s Produce script-friendly output. load Load the kernel module that implements the given class. This command is only available if the class does not yet exist in the kernel and the file geom_<class>.ko can be found in one of the directories specified in kern.module_path sysctl. unload Unload the kernel module which implements the given class. This command is only available if the given class is loaded as a kernel module. Class-specific commands are implemented as shared libraries which are stored in /lib/geom/ directory and are loaded via dlopen(3) function when the class name is known. When a class-specific shared library exists, a direct utility should also be available under the name of gclass. Currently available classes which are aware of geom(8): o CACHE o CONCAT o ELI o JOURNAL o LABEL o MIRROR o MOUNTVER o MULTIPATH o NOP o PART o RAID o RAID3 o SCHED o SHSEC o STRIPE o VIRSTOR ENVIRONMENT
The following environment variables affect the execution of geom: GEOM_LIBRARY_PATH Specifies the path where shared libraries are stored instead of /lib/geom/. Multiple paths can be specified with a colon- separated list of paths. EXIT STATUS
Exit status is 0 on success, and 1 if the command fails. EXAMPLES
The following example shows how to set up a stripe on three disks for automatic configuration: geom stripe label -v -s 65536 data /dev/da0 /dev/da1 /dev/da2 or: gstripe label -v -s 65536 data /dev/da0 /dev/da1 /dev/da2 Print the list of all providers from the DISK class: geom disk list Unload a kernel module which implements the MD class: geom md unload SEE ALSO
libgeom(3), geom(4), gcache(8), gconcat(8), geli(8), gjournal(8), glabel(8), gmirror(8), gmountver(8), gmultipath(8), gnop(8), gpart(8), graid3(8), gsched(8), gshsec(8), gstripe(8), gvirstor(8) HISTORY
The geom utility appeared in FreeBSD 5.3. AUTHORS
Pawel Jakub Dawidek <pjd@FreeBSD.org> BSD
January 5, 2011 BSD

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G_GEOM(9)						   BSD Kernel Developer's Manual						 G_GEOM(9)

NAME
g_new_geomf, g_destroy_geom -- geom management SYNOPSIS
#include <geom/geom.h> struct g_geom * g_new_geomf(struct g_class *mp, const char *fmt, ...); void g_destroy_geom(struct g_geom *gp); DESCRIPTION
The geom (do not confuse ``geom'' with ``GEOM'') is an instance of a GEOM class. For example: in a typical i386 FreeBSD system, there will be one geom of class MBR for each disk. The geom's name is not really important, it is only used in the XML dump and for debugging purposes. There can be many geoms with the same name. The g_new_geomf() function creates a new geom, which will be an instance of the class mp. The geom's name is created in a printf(3)-like way from the rest of the arguments. The g_destroy_geom() function destroys the given geom immediately and cancels all related pending events. The g_geom structure contains fields that should be set by the caller after geom creation, but before creating any providers or consumers related to this geom (not all are required): g_start_t * start Pointer to a function used for I/O processing. g_spoiled_t * spoiled Pointer to a function used for consumers spoiling. g_dumpconf_t * dumpconf Pointer to a function used for configuration in XML format dumping. g_access_t * access Pointer to a function used for access control. g_orphan_t * orphan Pointer to a function used to inform about orphaned consumer. g_ioctl_t * ioctl Pointer to a function used for handling ioctl requests. void * softc Field for private use. RESTRICTIONS
/CONDITIONS If you intend to use providers in this geom you must set field start of your geom. If you are planning to use consumers in your geom you must set fields orphan and access for it. g_new_geomf(): Class mp must be valid (registered in GEOM). The topology lock has to be held. g_destroy_geom(): The geom cannot posses any providers. The geom cannot posses any consumers. The topology lock has to be held. RETURN VALUES
The g_new_geomf() function returns a pointer to the newly created geom. EXAMPLES
Create an example geom. static struct geom * g_example_start(struct bio *bp) { [...] } static void g_example_orphan(struct g_consumer *cp) { g_topology_assert(); [...] } static void g_example_spoiled(struct g_consumer *cp) { g_topology_assert(); [...] } static void g_example_access(struct g_provider *pp, int dr, int dw, int de) { [...] } static struct g_geom * create_example_geom(struct g_class *myclass) { struct g_geom *gp; g_topology_lock(); gp = g_new_geomf(myclass, "example_geom"); g_topology_unlock(); gp->start = g_example_start; gp->orphan = g_example_orphan; gp->spoiled = g_example_spoiled; gp->access = g_example_access; gp->softc = NULL; return (gp); } static int destroy_example_geom(struct g_geom *gp) { g_topology_lock(); if (!LIST_EMPTY(&gp->provider) || !LIST_EMPTY(&gp->consumer)) { g_topology_unlock(); return (EBUSY); } g_destroy_geom(gp); g_topology_unlock(); return (0); } SEE ALSO
geom(4), DECLARE_GEOM_CLASS(9), g_access(9), g_attach(9), g_bio(9), g_consumer(9), g_data(9), g_event(9), g_provider(9), g_provider_by_name(9), g_wither_geom(9) AUTHORS
This manual page was written by Pawel Jakub Dawidek <pjd@FreeBSD.org>. BSD
January 16, 2004 BSD

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