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NAME

       sysctl - configure kernel parameters at runtime

SYNOPSIS

       sysctl [-n] [-e] variable ...
       sysctl [-n] [-e] [-q] -w variable=value ...
       sysctl [-n] [-e] [-q] -p [filename]
       sysctl [-n] [-e] -a
       sysctl [-n] [-e] -A

DESCRIPTION

       sysctl  is used to modify kernel parameters at runtime.  The parameters
       available are those listed under /proc/sys/.  Procfs  is  required  for
       sysctl  support  in  Linux.   You can use sysctl to both read and write
       sysctl data.

PARAMETERS

       variable
              The name of a key to read from.  An  example  is  kernel.ostype.
              The ’/’ separator is also accepted in place of a ’.’.

       variable=value
              To  set a key, use the form variable=value where variable is the
              key and value is the value to set it to.  If the value  contains
              quotes or characters which are parsed by the shell, you may need
              to enclose the value in double quotes.   This  requires  the  -w
              parameter to use.

       -n     Use  this  option  to  disable  printing  of  the  key name when
              printing values.

       -e     Use this option to ignore errors about unknown keys.

       -N     Use this option to only print the names. It may be  useful  with
              shells that have programmable completion.

       -q     Use this option to not display the values set to stdout.

       -w     Use this option when you want to change a sysctl setting.

       -p     Load   in   sysctl   settings   from   the   file  specified  or
              /etc/sysctl.conf if none given.  Specifying - as filename  means
              reading data from standard input.

       -a     Display all values currently available.

       -A     Display all values currently available in table form.

EXAMPLES

       /sbin/sysctl -a
       /sbin/sysctl -n kernel.hostname
       /sbin/sysctl -w kernel.domainname="example.com"
       /sbin/sysctl -p /etc/sysctl.conf

FILES

       /proc/sys
       /etc/sysctl.conf

SEE ALSO

       sysctl.conf(5)

BUGS

       The -A parameter behaves just as -a does.

AUTHOR

       George Staikos, <staikos@0wned.org>

                                  21 Sep 1999