tripathysagar/man_text huggingface dataset:
# mem

## NAME



           mem, kmem, port - system memory, kernel memory and system ports
    


## DESCRIPTION



           _/dev/mem_ is a character device file that is an image of the main
           memory of the computer.  It may be used, for example, to examine
           (and even patch) the system.
    
           Byte addresses in _/dev/mem_ are interpreted as physical memory
           addresses.  References to nonexistent locations cause errors to be
           returned.
    
           Examining and patching is likely to lead to unexpected results
           when read-only or write-only bits are present.
    
           Since Linux 2.6.26, and depending on the architecture, the
           **CONFIG_STRICT_DEVMEM** kernel configuration option limits the areas
           which can be accessed through this file.  For example: on x86, RAM
           access is not allowed but accessing memory-mapped PCI regions is.
    
           It is typically created by:
    
               mknod -m 660 /dev/mem c 1 1
               chown root:kmem /dev/mem
    
           The file _/dev/kmem_ is the same as _/dev/mem_ , except that the kernel
           virtual memory rather than physical memory is accessed.  Since
           Linux 2.6.26, this file is available only if the **CONFIG_DEVKMEM**
           kernel configuration option is enabled.
    
           It is typically created by:
    
               mknod -m 640 /dev/kmem c 1 2
               chown root:kmem /dev/kmem
    
           _/dev/port_ is similar to _/dev/mem_ , but the I/O ports are accessed.
    
           It is typically created by:
    
               mknod -m 660 /dev/port c 1 4
               chown root:kmem /dev/port
    


## FILES



           _/dev/mem_
           _/dev/kmem_
           _/dev/port_
    


* * *
# cpuid

## NAME



           cpuid - x86 CPUID access device
    


## DESCRIPTION



           CPUID provides an interface for querying information about the x86
           CPU.
    
           This device is accessed by lseek(2) or pread(2) to the appropriate
           CPUID level and reading in chunks of 16 bytes.  A larger read size
           means multiple reads of consecutive levels.
    
           The lower 32 bits of the file position is used as the incoming
           _%eax_ , and the upper 32 bits of the file position as the incoming
           _%ecx_ , the latter is intended for "counting" _eax_ levels like _eax=4_.
    
           This driver uses _/dev/cpu/CPUNUM/cpuid_ , where _CPUNUM_ is the minor
           number, and on an SMP box will direct the access to CPU _CPUNUM_ as
           listed in _/proc/cpuinfo_.
    
           This file is protected so that it can be read only by the user
           _root_ , or members of the group _root_.
    


## NOTES



           The CPUID instruction can be directly executed by a program using
           inline assembler.  However this device allows convenient access to
           all CPUs without changing process affinity.
    
           Most of the information in _cpuid_ is reported by the kernel in
           cooked form either in _/proc/cpuinfo_ or through subdirectories in
           _/sys/devices/system/cpu_.  Direct CPUID access through this device
           should only be used in exceptional cases.
    
           The _cpuid_ driver is not auto-loaded.  On modular kernels you might
           need to use the following command to load it explicitly before
           use:
    
               $ modprobe cpuid
    
           There is no support for CPUID functions that require additional
           input registers.
    
           Early i486 CPUs do not support the CPUID instruction; opening this
           device for those CPUs fails with EIO.
    


* * *
# ram

## NAME



           ram - ram disk device
    


## DESCRIPTION



           The _ram_ device is a block device to access the ram disk in raw
           mode.
    
           It is typically created by:
    
               mknod -m 660 /dev/ram b 1 1
               chown root:disk /dev/ram
    


## FILES



           _/dev/ram_
    


* * *
# veth

## NAME



           veth - Virtual Ethernet Device
    


## DESCRIPTION



           The **veth** devices are virtual Ethernet devices.  They can act as
           tunnels between network namespaces to create a bridge to a
           physical network device in another namespace, but can also be used
           as standalone network devices.
    
           **veth** devices are always created in interconnected pairs.  A pair
           can be created using the command:
    
               # ip link add <p1-name> type veth peer name <p2-name>
    
           In the above, _p1-name_ and _p2-name_ are the names assigned to the
           two connected end points.
    
           Packets transmitted on one device in the pair are immediately
           received on the other device.  When either device is down, the
           link state of the pair is down.
    
           **veth** device pairs are useful for combining the network facilities
           of the kernel together in interesting ways.  A particularly
           interesting use case is to place one end of a **veth** pair in one
           network namespace and the other end in another network namespace,
           thus allowing communication between network namespaces.  To do
           this, one can provide the **netns** parameter when creating the
           interfaces:
    
               # ip link add <p1-name> netns <p1-ns> type veth peer <p2-name> netns <p2-ns>
    
           or, for an existing **veth** pair, move one side to the other
           namespace:
    
               # ip link set <p2-name> netns <p2-ns>
    
           ethtool(8) can be used to find the peer of a **veth** network
           interface, using commands something like:
    
               # **ip link add ve_A type veth peer name ve_B** ;   # Create veth pair
               # **ethtool -S ve_A** ;         # Discover interface index of peer
               NIC statistics:
                    peer_ifindex: 16
               # **ip link | grep '^16:'** ;   # Look up interface
               16: ve_B@ve_A: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc ...
    


* * *
# intro

## NAME



           intro - introduction to special files
    


## DESCRIPTION



           Section 4 of the manual describes special files (devices).
    


## FILES



           /dev/* — device files
    


## NOTES



       **Authors and copyright conditions**
           Look at the header of the manual page source for the author(s) and
           copyright conditions.  Note that these can be different from page
           to page!
    


* * *
# ttyS

## NAME



           ttyS - serial terminal lines
    


## DESCRIPTION



           **ttyS[0-3]** are character devices for the serial terminal lines.
    
           They are typically created by:
    
               mknod -m 660 /dev/ttyS0 c 4 64 # base address 0x3f8
               mknod -m 660 /dev/ttyS1 c 4 65 # base address 0x2f8
               mknod -m 660 /dev/ttyS2 c 4 66 # base address 0x3e8
               mknod -m 660 /dev/ttyS3 c 4 67 # base address 0x2e8
               chown root:tty /dev/ttyS[0-3]
    


## FILES



           _/dev/ttyS[0-3]_
    


* * *
# tty

## NAME



           tty - controlling terminal
    


## DESCRIPTION



           The file _/dev/tty_ is a character file with major number 5 and
           minor number 0, usually with mode 0666 and ownership root:tty.  It
           is a synonym for the controlling terminal of a process, if any.
    
           In addition to the ioctl(2) requests supported by the device that
           **tty** refers to, the ioctl(2) request **TIOCNOTTY** is supported.
    
       **TIOCNOTTY**
           Detach the calling process from its controlling terminal.
    
           If the process is the session leader, then **SIGHUP** and **SIGCONT**
           signals are sent to the foreground process group and all processes
           in the current session lose their controlling tty.
    
           This ioctl(2) call works only on file descriptors connected to
           _/dev/tty_.  It is used by daemon processes when they are invoked by
           a user at a terminal.  The process attempts to open _/dev/tty_.  If
           the open succeeds, it detaches itself from the terminal by using
           **TIOCNOTTY** , while if the open fails, it is obviously not attached
           to a terminal and does not need to detach itself.
    


## FILES



           _/dev/tty_
    


* * *
# null

## NAME



           null, zero - data sink
    


## DESCRIPTION



           Data written to the _/dev/null_ and _/dev/zero_ special files is
           discarded.
    
           Reads from _/dev/null_ always return end of file (i.e., read(2)
           returns 0), whereas reads from _/dev/zero_ always return bytes
           containing zero ('\0' characters).
    
           These devices are typically created by:
    
               mknod -m 666 /dev/null c 1 3
               mknod -m 666 /dev/zero c 1 5
               chown root:root /dev/null /dev/zero
    


## FILES



           _/dev/null_
           _/dev/zero_
    


## NOTES



           If these devices are not writable and readable for all users, many
           programs will act strangely.
    
           Since Linux 2.6.31, reads from _/dev/zero_ are interruptible by
           signals.  (This change was made to help with bad latencies for
           large reads from _/dev/zero_.)
    


* * *
# pts

## NAME



           ptmx, pts - pseudoterminal master and slave
    


## DESCRIPTION



           The file _/dev/ptmx_ (the pseudoterminal multiplexor device) is a
           character file with major number 5 and minor number 2, usually
           with mode 0666 and ownership root:root.  It is used to create a
           pseudoterminal master and slave pair.
    
           When a process opens _/dev/ptmx_ , it gets a file descriptor for a
           pseudoterminal master and a pseudoterminal slave device is created
           in the _/dev/pts_ directory.  Each file descriptor obtained by
           opening _/dev/ptmx_ is an independent pseudoterminal master with its
           own associated slave, whose path can be found by passing the file
           descriptor to ptsname(3).
    
           Before opening the pseudoterminal slave, you must pass the
           master's file descriptor to grantpt(3) and unlockpt(3).
    
           Once both the pseudoterminal master and slave are open, the slave
           provides processes with an interface that is identical to that of
           a real terminal.
    
           Data written to the slave is presented on the master file
           descriptor as input.  Data written to the master is presented to
           the slave as input.
    
           In practice, pseudoterminals are used for implementing terminal
           emulators such as **xterm**(1), in which data read from the
           pseudoterminal master is interpreted by the application in the
           same way a real terminal would interpret the data, and for
           implementing remote-login programs such as sshd(8), in which data
           read from the pseudoterminal master is sent across the network to
           a client program that is connected to a terminal or terminal
           emulator.
    
           Pseudoterminals can also be used to send input to programs that
           normally refuse to read input from pipes (such as su(1), and
           passwd(1)).
    


## FILES



           _/dev/ptmx_ , _/dev/pts/*_
    


## NOTES



           The Linux support for the above (known as UNIX 98 pseudoterminal
           naming) is done using the _devpts_ filesystem, which should be
           mounted on _/dev/pts_.
    


* * *
# full

## NAME



           full - always full device
    


## CONFIGURATION



           If your system does not have _/dev/full_ created already, it can be
           created with the following commands:
    
               mknod -m 666 /dev/full c 1 7
               chown root:root /dev/full
    


## DESCRIPTION



           The file _/dev/full_ has major device number 1 and minor device
           number 7.
    
           Writes to the _/dev/full_ device fail with an **ENOSPC** error.  This
           can be used to test how a program handles disk-full errors.
    
           Reads from the _/dev/full_ device will return \0 characters.
    
           Seeks on _/dev/full_ will always succeed.
    


## FILES



           _/dev/full_
    


* * *
# ioctl_console

## NAME



           ioctl_console - ioctls for console terminal and virtual consoles
    


## SYNOPSIS



           **#include <sys/ioctl.h>**
    
           **int ioctl(int** _fd_**, unsigned long** _op_**, ...);**
    


## DESCRIPTION



           The following Linux-specific ioctl(2) operations are supported for
           console terminals and virtual consoles.
    
           KDGETLED(2const)
           KDSETLED(2const)
           KDGKBLED(2const)
           KDSKBLED(2const)
           KDGKBTYPE(2const)
           KDADDIO(2const)
           KDDELIO(2const)
           KDENABIO(2const)
           KDDISABIO(2const)
           KDSETMODE(2const)
           KDGETMODE(2const)
           KDMKTONE(2const)
           KIOCSOUND(2const)
           GIO_CMAP(2const)
           PIO_CMAP(2const)
           GIO_FONT(2const)
           GIO_FONTX(2const)
           PIO_FONT(2const)
           PIO_FONTX(2const)
           PIO_FONTRESET(2const)
           GIO_SCRNMAP(2const)
           GIO_UNISCRNMAP(2const)
           PIO_SCRNMAP(2const)
           PIO_UNISCRNMAP(2const)
           GIO_UNIMAP(2const)
           PIO_UNIMAP(2const)
           PIO_UNIMAPCLR(2const)
           KDGKBMODE(2const)
           KDSKBMODE(2const)
           KDGKBMETA(2const)
           KDSKBMETA(2const)
           KDGKBENT(2const)
           KDSKBENT(2const)
           KDGKBSENT(2const)
           KDSKBSENT(2const)
           KDGKBDIACR(2const)
           KDGETKEYCODE(2const)
           KDSETKEYCODE(2const)
           KDSIGACCEPT(2const)
                  See ioctl_kd(2).
    
           TIOCLINUX(2const)
    
           VT_OPENQRY(2const)
           VT_GETMODE(2const)
           VT_SETMODE(2const)
           VT_GETSTATE(2const)
           VT_RELDISP(2const)
           VT_ACTIVATE(2const)
           VT_WAITACTIVE(2const)
           VT_DISALLOCATE(2const)
           VT_RESIZE(2const)
           VT_RESIZEX(2const)
                  See ioctl_vt(2).
    


## RETURN VALUE



           On success, 0 is returned (except where indicated).  On failure,
           -1 is returned, and _errno_ is set to indicate the error.
    


## STANDARDS



           Linux.
    


## CAVEATS



           Do not regard this man page as documentation of the Linux console
           ioctls.  This is provided for the curious only, as an alternative
           to reading the source.  Ioctl's are undocumented Linux internals,
           liable to be changed without warning.  (And indeed, this page more
           or less describes the situation as of kernel version 1.1.94; there
           are many minor and not-so-minor differences with earlier
           versions.)
    
           Very often, ioctls are introduced for communication between the
           kernel and one particular well-known program (fdisk, hdparm,
           setserial, tunelp, loadkeys, selection, setfont, etc.), and their
           behavior will be changed when required by this particular program.
    


* * *
# msr

## NAME



           msr - x86 CPU MSR access device
    


## DESCRIPTION



           _/dev/cpu/CPUNUM/msr_ provides an interface to read and write the
           model-specific registers (MSRs) of an x86 CPU.  _CPUNUM_ is the
           number of the CPU to access as listed in _/proc/cpuinfo_.
    
           The register access is done by opening the file and seeking to the
           MSR number as offset in the file, and then reading or writing in
           chunks of 8 bytes.  An I/O transfer of more than 8 bytes means
           multiple reads or writes of the same register.
    
           This file is protected so that it can be read and written only by
           the user _root_ , or members of the group _root_.
    


## NOTES



           The _msr_ driver is not auto-loaded.  On modular kernels you might
           need to use the following command to load it explicitly before
           use:
    
               $ modprobe msr
    


* * *
# hd

## NAME



           hd - MFM/IDE hard disk devices
    


## DESCRIPTION



           The **hd*** devices are block devices to access MFM/IDE hard disk
           drives in raw mode.  The master drive on the primary IDE
           controller (major device number 3) is **hda** ; the slave drive is **hdb**.
           The master drive of the second controller (major device number 22)
           is **hdc** and the slave is **hdd**.
    
           General IDE block device names have the form **hd** _X_ , or **hd** _XP_ , where _X_
           is a letter denoting the physical drive, and _P_ is a number
           denoting the partition on that physical drive.  The first form,
           **hd** _X_ , is used to address the whole drive.  Partition numbers are
           assigned in the order the partitions are discovered, and only
           nonempty, nonextended partitions get a number.  However, partition
           numbers 1–4 are given to the four partitions described in the MBR
           (the "primary" partitions), regardless of whether they are unused
           or extended.  Thus, the first logical partition will be **hd** _X_**5**.
           Both DOS-type partitioning and BSD-disklabel partitioning are
           supported.  You can have at most 63 partitions on an IDE disk.
    
           For example, _/dev/hda_ refers to all of the first IDE drive in the
           system; and _/dev/hdb3_ refers to the third DOS "primary" partition
           on the second one.
    
           They are typically created by:
    
               mknod -m 660 /dev/hda b 3 0
               mknod -m 660 /dev/hda1 b 3 1
               mknod -m 660 /dev/hda2 b 3 2
               ...
               mknod -m 660 /dev/hda8 b 3 8
               mknod -m 660 /dev/hdb b 3 64
               mknod -m 660 /dev/hdb1 b 3 65
               mknod -m 660 /dev/hdb2 b 3 66
               ...
               mknod -m 660 /dev/hdb8 b 3 72
               chown root:disk /dev/hd*
    


## FILES



           _/dev/hd*_
    


* * *
# ioctl_tty

## NAME



           ioctl_tty - ioctls for terminals and serial lines
    


## LIBRARY



           Standard C library (_libc_ , _-lc_)
    


## SYNOPSIS



           **#include <asm/termbits.h>  **/* Definition of constants */
           **#include <sys/ioctl.h>**
    
           **int ioctl(int** _fd_**, int** _op_**, ...);**
    


## DESCRIPTION



           The ioctl(2) call for terminals and serial ports accepts many
           possible operation arguments.  Most require a third argument, of
           varying type, here called _argp_ or _arg_.
    
           Use of **ioctl**() makes for nonportable programs.  Use the POSIX
           interface described in termios(3) whenever possible.
    
       **Get and set terminal attributes**
           TCGETS(2const)
           TCSETS(2const)
           TCSETSW(2const)
           TCSETSF(2const)
    
           TCGETS(2const)
           TCSETS(2const)
           TCSETSW(2const)
           TCSETSF(2const)
    
           TCGETS(2const)
           TCSETS(2const)
           TCSETSW(2const)
           TCSETSF(2const)
    
       **Locking the termios structure**
           TIOCGLCKTRMIOS(2const)
           TIOCSLCKTRMIOS(2const)
    
       **Get and set window size**
           TIOCGWINSZ(2const)
           TIOCSWINSZ(2const)
    
       **Sending a break**
           TCSBRK(2const)
           TCSBRKP(2const)
           TIOCSBRK(2const)
           TIOCCBRK(2const)
    
       **Software flow control**
           TCXONC(2const)
    
       **Buffer count and flushing**
           FIONREAD(2const)
           TIOCINQ(2const)
           TIOCOUTQ(2const)
           TCFLSH(2const)
           TIOCSERGETLSR(2const)
    
       **Faking input**
           TIOCSTI(2const)
    
       **Redirecting console output**
           TIOCCONS(2const)
    
       **Controlling terminal**
           TIOCSCTTY(2const)
           TIOCNOTTY(2const)
    
       **Process group and session ID**
           TIOCGPGRP(2const)
           TIOCSPGRP(2const)
           TIOCGSID(2const)
    
       **Exclusive mode**
           TIOCEXCL(2const)
           TIOCGEXCL(2const)
           TIOCNXCL(2const)
    
       **Line discipline**
           TIOCGETD(2const)
           TIOCSETD(2const)
    
       **Pseudoterminal ioctls**
           TIOCPKT(2const)
           TIOCGPKT(2const)
    
           TIOCSPTLCK(2const)
           TIOCGPTLCK(2const)
    
           TIOCGPTPEER(2const)
    
       **Modem control**
           TIOCMGET(2const)
           TIOCMSET(2const)
           TIOCMBIC(2const)
           TIOCMBIS(2const)
    
           TIOCMIWAIT(2const)
    
           TIOCGICOUNT(2const)
    
       **Marking a line as local**
           TIOCGSOFTCAR(2const)
           TIOCSSOFTCAR(2const)
    
       **Linux-specific**
           For the TIOCLINUX(2const) ioctl, see ioctl_console(2).
    
       **Kernel debugging**
           TIOCTTYGSTRUCT(2const)
    


## RETURN VALUE



           On success, 0 is returned.  On error, -1 is returned, and _errno_ is
           set to indicate the error.
    


* * *
# systemd-portabled.service

## NAME



           systemd-portabled.service, systemd-portabled - Portable service
           manager
    


## SYNOPSIS



           systemd-portabled.service
    
           /usr/lib/systemd/systemd-portabled
    


## DESCRIPTION



           **systemd-portabled** is a system service that may be used to attach,
           detach and inspect portable service images.
    
           Most of **systemd-portabled** 's functionality is accessible through
           the portablectl(1) command.
    
           See the **Portable Services******[1] page for details about the concepts
           this service implements.
    
           Seeorg.freedesktop.portable1(5) and
           org.freedesktop.LogControl1(5) for a description of the D-Bus API.
    


## NOTES



            1. Portable Services
               https://systemd.io/PORTABLE_SERVICES
    


* * *
# accton

## NAME



           accton -  turns process accounting on or off
    


## SYNOPSIS



           **accton**[_OPTION_] on**|** off**|** filename
    
           **accton**[ **-V** | **--version**] [ **-h** | **--help**]
    


## DESCRIPTION



           **accton** _filename_ turns on process accounting.
    


## OPTIONS



           **-V, --version**
                  Print the version number of **ac** to standard output and quit.
           **-h, --help**
                  Prints the usage string and default locations of system
                  files to standard output and exits.
           **on** Turns on process accounting using the default accounting
                  file name.
           **off** Turns off process accounting.
    


## FILES



           _acct_   The system wide process accounting file. See acct(5) (or
                  **pacct**(5)) for further details.
    


* * *
# ibprintswitch

## NAME



           ibprintswitch.pl - print either the switch specified or a list of
           switches from the ibnetdiscover output
    


## SYNOPSIS



           **ibprintswitch.pl**[-R -l -C <ca_name> -P <ca_port>]
           [<switch_guid|switch_name>]
    


## DESCRIPTION



           Faster than greping/viewing with an editor the output of
           ibnetdiscover, ibprintswitch.pl will parse out and print either
           the switch information for the switch specified or a list of all
           the switches found in the subnet.  In addition, it will crudely
           parse on the node description information and if found report all
           the information for an entire chasis if the description
           information is consistent.
    
           Finally, ibprintswitch.pl will also reuse the cached ibnetdiscover
           output from some of the other diag tools which makes it a bit
           faster than running ibnetdiscover from scratch.
    


## OPTIONS



           **-l** List the switches (simply a wrapper for ibswitches).
    
           **-R** Recalculate the ibnetdiscover information, ie do not use
                  the cached information.  This option is slower but should
                  be used if the diag tools have not been used for some time
                  or if there are other reasons to believe that the fabric
                  has changed.
    
           **-C <ca_name>    **use the specified ca_name for the search.
    
           **-P <ca_port>    **use the specified ca_port for the search.
    


* * *
# ibdatacounts

## NAME



           ibdatacounts - get IB port data counters
    


## SYNOPSIS



           **ibdatacounts**[-h] [-b] [-v] [-G] [-N | -nocolor] [-C ca_name] [-P
           ca_port] [-t(imeout) timeout_ms] <lid|guid> [<port>]
    


## DESCRIPTION



           Obtain PMA data counters from specified port (or node).  Port
           address is lid unless -G option is used to specify a GUID address.
    


## OPTIONS



           -G      use GUID address argument. In most cases, it is the Port
           GUID.
                   Example:
                   "0x08f1040023"
    
           -v      increase the verbosity level
    
           -b      brief mode
    
           -N | -nocolor use mono rather than color mode
    
           -C <ca_name>    use the specified ca_name.
    
           -P <ca_port>    use the specified ca_port.
    
           -t <timeout_ms> override the default timeout for the solicited
           mads.
    


## EXAMPLE



           ibdatacounts 2           # show data counters for lid 2
    
           ibdatacounts 2   4       # show data counters for lid 2 port 4
    


* * *
# systemd-timedated.service

## NAME



           systemd-timedated.service, systemd-timedated - Time and date bus
           mechanism
    


## SYNOPSIS



           systemd-timedated.service
    
           /usr/lib/systemd/systemd-timedated
    


## DESCRIPTION



           systemd-timedated.service is a system service that may be used as
           a mechanism to change the system clock and timezone, as well as to
           enable/disable network time synchronization.  systemd-timedated is
           automatically activated on request and terminates itself when it
           is unused.
    
           The tool timedatectl(1) is a command line client to this service.
    
           systemd-timedated currently offers access to the following four
           settings:
    
           •   The system time
    
           •   The system timezone
    
           •   A boolean controlling whether the system RTC is in local or
               UTC timezone
    
           •   Whether the time synchronization service is enabled/started or
               disabled/stopped, see next section.
    
           See org.freedesktop.timedate1(5) and
           org.freedesktop.LogControl1(5) for information about the D-Bus
           API.
    


## LIST OF NETWORK TIME SYNCHRONIZATION SERVICES



           **systemd-timedated** will look for files with a ".list" extension in
           ntp-units.d/ directories. Each file is parsed as a list of unit
           names, one per line. Empty lines and lines with comments ("#") are
           ignored. Files are read from /usr/lib/systemd/ntp-units.d/ and the
           corresponding directories under /etc/, /run/, /usr/local/lib/.
           Files in /etc/ override files with the same name in /run/,
           /usr/local/lib/, and /usr/lib/. Files in /run/ override files with
           the same name under /usr/. Packages should install their
           configuration files in /usr/lib/ (distribution packages) or
           /usr/local/lib/ (local installs).
    
           **Example 1. ntp-units.d/ entry for systemd-timesyncd**
    
               # /usr/lib/systemd/ntp-units.d/80-systemd-timesync.list
               systemd-timesyncd.service
    
           If the environment variable _$SYSTEMD_TIMEDATED_NTP_SERVICES_ is
           set, **systemd-timedated** will parse the contents of that variable as
           a colon-separated list of unit names. When set, this variable
           overrides the file-based list described above.
    
           **Example 2. An override that specifies that chronyd should be used**
           **if available**
    
               SYSTEMD_TIMEDATED_NTP_SERVICES=chronyd.service:systemd-timesyncd.service
    


* * *
# rpmkeys

## NAME



           rpmkeys - RPM Keyring
    


## SYNOPSIS



           **rpmkeys**{**--list|--import|--erase|--delete|--checksig**}
    


## DESCRIPTION



           The general forms of rpm(8) digital signature commands are
    
           **rpmkeys**{**-l|--list**} [_FINGERPRINT ..._]
    
           **rpmkeys**{**-x|--export**} [_FINGERPRINT ..._]
    
           **rpmkeys**{**-i|--import**} _PUBKEY ..._
    
           **rpmkeys**{**-e|--erase|-d|--delete**} _FINGERPRINT ..._
    
           **rpmkeys**{**-K|--checksig**} _PACKAGE_FILE ..._
    
           The **--checksig** option checks all the digests and signatures
           contained in _PACKAGE_FILE_ to ensure the integrity and origin of
           the package.  Note that signatures are now verified whenever a
           package is read, and **--checksig** is useful to verify all of the
           digests and signatures associated with a package.
    
           Digital signatures cannot be verified without a public key.  An
           ASCII armored public key can be added to the **rpm** persistent
           keyring using **--import**.
    
           The following commands are available for manipulating the
           persistent rpm keyring:
    
           **rpmkeys**{**-l|--list**} [_FINGERPRINT ..._]
    
           List currently imported public key(s) (aka certificates) by their
           fingerprint and user ID.  If no fingerprints are specified, list
           all keys.
    
           The fingerprint is the handle used for all operations on the keys.
    
           **rpmkeys**{**-x|--export**} [_FINGERPRINT ..._]
    
           Output the key(s) using an ASCII-armor encoding.
    
           Exporting allows for inspecting the data with specialized tools,
           such as Sequoia or GnuPG.  For example:
    
           **rpmkeys –export 771b18d3d7baa28734333c424344591e1964c5fc | sq**
           **inspect**
    
           **rpmkeys**{**-e|--erase|-d|--delete**} _FINGERPRINT ..._
    
           Erase the key(s) designated by _FINGERPRINT_.  For example:
    
           **rpmkeys --erase 771b18d3d7baa28734333c424344591e1964c5fc**
    


* * *
# tc-matchall

## NAME



           matchall - traffic control filter that matches every packet
    


## SYNOPSIS



           **tc filter**... **matchall**[ **skip_sw** | **skip_hw**] [ **action** _ACTION_SPEC_
                   ] [ **classid** _CLASSID_ ]
    


## DESCRIPTION



           The **matchall** filter allows one to classify every packet that flows
           on the port and run a action on it.
    


## OPTIONS



           **action** _ACTION_SPEC_
                  Apply an action from the generic actions framework on
                  matching packets.
    
           **classid** _CLASSID_
                  Push matching packets into the class identified by _CLASSID_.
    
           **skip_sw**
                  Do not process filter by software. If hardware has no
                  offload support for this filter, or TC offload is not
                  enabled for the interface, operation will fail.
    
           **skip_hw**
                  Do not process filter by hardware.
    


## EXAMPLES



           To create ingress mirroring from port eth1 to port eth2:
    
                  tc qdisc  add dev eth1 handle ffff: clsact
                  tc filter add dev eth1 ingress                \
                          matchall skip_sw                      \
                          action mirred egress mirror           \
                          dev eth2
    
           The first command creates a clsact qdisc with handle **ffff:** on
           device **eth1** where the second command attaches a matchall filters
           on it that mirrors the packets to device eth2 for ingress.
    
           To create egress mirroring from port eth1 to port eth2:
    
                  tc qdisc add dev eth1 handle ffff: clsact
                  tc filter add dev eth1 egress                  \
                          matchall skip_sw                       \
                          action mirred egress mirror            \
                          dev eth2
    
           The first command creates a clsact qdisc with handle **ffff:** on
           device **eth1** where the second command attaches a matchall filters
           on it that mirrors the packets to device eth2 for egress.
    
           To sample one of every 100 packets flowing into interface eth0 to
           psample group 12:
    
                  tc qdisc add dev eth0 handle ffff: ingress
                  tc filter add dev eth0 parent ffff: matchall \
                       action sample rate 100 group 12
    


* * *
# ip-mroute

## NAME



           ip-mroute - multicast routing cache management
    


## SYNOPSIS



           **ip mroute show**[ [  **to**] _PREFIX_ ] [ **from** _PREFIX_ ] [ **iif** _DEVICE_ ]
                   [ **table** _TABLE_ID_ ]
    


## DESCRIPTION



           **mroute** objects are multicast routing cache entries created by a
           user-level mrouting daemon (f.e.  **pimd** or **mrouted**).
    
           Due to the limitations of the current interface to the multicast
           routing engine, it is impossible to change **mroute** objects
           administratively, so we can only display them. This limitation
           will be removed in the future.
    
       **ip mroute show - list mroute cache entries**
           **to** _PREFIX_ **(default)**
                  the prefix selecting the destination multicast addresses to
                  list.
    
           **iif** _NAME_
                  the interface on which multicast packets are received.
    
           **from** _PREFIX_
                  the prefix selecting the IP source addresses of the
                  multicast route.
    
           **table** _TABLE_ID_
                  the table id selecting the multicast table. It can be
                  **local** , **main** , **default** , **all** or a number.
    


* * *
# rmmod

## NAME



           rmmod - Simple program to remove a module from the Linux Kernel
    


## SYNOPSIS



           **rmmod**[_OPTIONS_] [_list of modulenames_]
    


## DESCRIPTION



           **rmmod** is a trivial program to remove a module or a list of modules
           from the kernel (when module unloading support is provided). Most
           users will want to use modprobe(8) with the **-r** option instead
           since it removes unused dependent modules as well.
    
           When a list of modules is provided, the program will process them
           one at a time. If a module is not found, **rmmod** will immediately
           exit with an error code. Should the module removal fail, the
           program will log an error AND continue with the next module. This
           behaviour is NOT controlled by the **--force** option.
    


## OPTIONS



           **-f** , **--force**
               This option can be extremely dangerous: it has no effect
               unless CONFIG_MODULE_FORCE_UNLOAD was set when the kernel was
               compiled. With this option, you can remove modules which are
               being used, or which are not designed to be removed, or have
               been marked as unsafe (see lsmod(8)).
    
           **-s** , **--syslog**
               Send errors to syslog instead of standard error.
    
           **-v** , **--verbose**
               Print messages about what the program is doing. Usually **rmmod**
               prints messages only if something goes wrong.
    
           **-V** , **--version**
               Show version of program and exit.
    
           **-h** , **--help**
               Print the help message and exit.
    


## BUGS



           Please direct any bug reports to kmod's issue tracker at
           https://github.com/kmod-project/kmod/issues/ alongside with
           version used, steps to reproduce the problem and the expected
           outcome.
    


* * *
# systemd-update-done.service

## NAME



           systemd-update-done.service, systemd-update-done - Mark /etc/ and
           /var/ as fully updated
    


## SYNOPSIS



           systemd-update-done.service
    
           /usr/lib/systemd/systemd-update-done
    


## DESCRIPTION



           systemd-update-done.service is a service that is invoked as part
           of the first boot after the vendor operating system resources in
           /usr/ have been updated. This is useful to implement offline
           updates of /usr/ which might require updates to /etc/ or /var/ on
           the following boot.
    
           systemd-update-done.service updates the file modification time
           (mtime) stored in and "on" the files /etc/.updated and
           /var/.updated to the modification time of the /usr/ directory,
           unless the stamp files are already newer. (The timestamp is stored
           as the mtime field on the file, but also _in_ the file to support
           filesystems that do not store full timestamp precision.)
    
           Services that shall run after offline upgrades of /usr/ should
           order themselves before systemd-update-done.service, and use the
           _ConditionNeedsUpdate=_ (see systemd.unit(5)) condition to make sure
           to run when /etc/ or /var/ are older than /usr/ according to the
           modification times of the files described above. This requires
           that updates to /usr/ are always followed by an update of the
           modification time of /usr/, for example by invoking touch(1) on
           it.
    
           Note that if the _systemd.condition_needs_update=_ kernel command
           line option is used it overrides the _ConditionNeedsUpdate=_ unit
           condition checks. In that case systemd-update-done.service will
           not reset the condition state until a follow-up reboot where the
           kernel switch is not specified anymore.
    


## OPTIONS



           The following options are understood:
    
           **--root=**_root_
               Takes a directory path as an argument. The program will
               operate on paths below the specified root directory.
    
               Added in version 258.
    
           **-h** , **--help**
               Print a short help text and exit.
    


* * *
# pam_cifscreds

## NAME



           pam_cifscreds - PAM module to manage NTLM credentials in kernel
           keyring
    


## SYNOPSIS



           Edit the PAM configuration files for the systems that you want to
           automatically register NTLM credentials for, e.g.
           _/etc/pam.d/login_ , and modify as follows:
    
                  ...
                  auth       substack     system-auth
              +++ auth       optional     pam_cifscreds.so
                  auth       include      postlogin
                  ...
    
                  ...
                  session    include      system-auth
              +++ session    optional     pam_cifscreds.so domain=DOMAIN
                  session    include      postlogin
                  ...
    
           Change DOMAIN to the name of you Windows domain, or use host= as
           described below.
    


## DESCRIPTION



           The **pam_cifscreds** PAM module is a tool for automatically adding
           credentials (username and password) for the purpose of
           establishing sessions in multiuser mounts.
    
           When a cifs filesystem is mounted with the "multiuser" option, and
           does not use krb5 authentication, it needs to be able to get the
           credentials for each user from somewhere. The **pam_cifscreds** module
           can be used to provide these credentials to the kernel
           automatically at login.
    
           In the session section of the PAM configuration file, the module
           can either an NT domain name or a list of hostname or addresses.
    


## OPTIONS



           **pam_cifscreds** supports a couple options which can be set in the
           PAM configuration files. You must have one (and only one) of
           **domain=** or **host=**.
    
           **debug** Turns on some extra debug logging.
    
           **domain= <NT domain name>**
                  Credentials will be added for the specified NT domain name.
    
           **host= <hostname or IP address>[,...]**
                  Credentials will be added for the specified hostnames or IP
                  addresses.
    


## NOTES



           The pam_cifscreds PAM module requires a kernel built with support
           for the **login** key type. That key type was added in v3.3 in
           mainline Linux kernels.
    
           Since **pam_cifscreds** adds keys to the session keyring, it is highly
           recommended that one use **pam_keyinit** to ensure that a session
           keyring is established at login time.
    


* * *
# sln

## NAME



           sln - create symbolic links
    


## SYNOPSIS



           **sln** _source dest_
           **sln** _filelist_
    


## DESCRIPTION



           The **sln** program creates symbolic links.  Unlike the ln(1) program,
           it is statically linked.  This means that if for some reason the
           dynamic linker is not working, **sln** can be used to make symbolic
           links to dynamic libraries.
    
           The command line has two forms.  In the first form, it creates
           _dest_ as a new symbolic link to _source_.
    
           In the second form, _filelist_ is a list of space-separated pathname
           pairs, and the effect is as if **sln** was executed once for each line
           of the file, with the two pathnames as the arguments.
    
           The **sln** program supports no command-line options.
    


* * *
# systemd-importd.service

## NAME



           systemd-importd.service, systemd-importd - VM and container image
           import and export service
    


## SYNOPSIS



           systemd-importd.service
    
           /usr/lib/systemd/systemd-importd
    


## DESCRIPTION



           **systemd-importd** is a system service that allows importing,
           exporting and downloading of disk images. It provides the
           implementation for importctl(1)'s **pull-raw** , **pull-tar** , **import-raw** ,
           **import-tar** , **import-fs** , **export-raw** , and **export-tar** commands.
    
           See org.freedesktop.import1(5) and org.freedesktop.LogControl1(5)
           for a description of the D-Bus API.
    


* * *
# arptables-nft-save

## NAME



           arptables-save — dump arptables rules to stdout (nft-based)
    


## SYNOPSIS



           **arptables-save**[**-M** _modprobe_] [**-c**]
    
           **arptables-save**[**-V**]
    


## DESCRIPTION



           **arptables-save** is used to dump the contents of an ARP Table in
           easily parseable format to STDOUT. Use I/O-redirection provided by
           your shell to write to a file.
    
           **-M** , **--modprobe** _modprobe_program_
                  Specify the path to the modprobe program. By default,
                  arptables-save will inspect /proc/sys/kernel/modprobe to
                  determine the executable's path.
    
           **-c** , **--counters**
                  Include the current values of all packet and byte counters
                  in the output.
    
           **-V** , **--version**
                  Print version information and exit.
    


* * *
# tc-skbedit

## NAME



           skbedit - SKB editing action
    


## SYNOPSIS



           **tc**... **action skbedit**[ **queue_mapping** _QUEUE_MAPPING_ ] [ **priority**
                   _PRIORITY_ ] [ **mark** _MARK_[**/**_MASK] ] [_ **ptype** _PTYPE_ ] [
                   **inheritdsfield**]
    


## DESCRIPTION



           The **skbedit** action allows one to change a packet's associated meta
           data. It complements the **pedit** action, which in turn allows one to
           change parts of the packet data itself.
    
           The most unique feature of **skbedit** is its ability to decide over
           which queue of an interface with multiple transmit queues the
           packet is to be sent out. The number of available transmit queues
           is reflected by sysfs entries within
           _/sys/class/net/ <interface>/queues_ with name _tx-N_ (where _N_ is the
           actual queue number).
    


## OPTIONS



           **queue_mapping** _QUEUE_MAPPING_
                  Override the packet's transmit queue. Useful when applied
                  to packets transmitted over MQ-capable network interfaces.
                  _QUEUE_MAPPING_ is an unsigned 16bit value in decimal format.
    
           **priority** _PRIORITY_
                  Override the packet classification decision.  _PRIORITY_ is
                  either **root** , **none** or a hexadecimal major class ID
                  optionally followed by a colon (**:**) and a hexadecimal minor
                  class ID.
    
           **mark** _MARK_[**/**_MASK]_
                  Change the packet's firewall mark value.  _MARK_ is an
                  unsigned 32bit value in automatically detected format
                  (i.e., prefix with '**0x** ' for hexadecimal interpretation,
                  etc.).  _MASK_ defines the 32-bit mask selecting bits of mark
                  value. Default is 0xffffffff.
    
           **ptype** _PTYPE_
                  Override the packet's type. Useful for setting packet type
                  to host when needing to allow ingressing packets with the
                  wrong MAC address but correct IP address.  _PTYPE_ is one of:
                  host, otherhost, broadcast, multicast
    
           **inheritdsfield**
                  Override the packet classification decision, and any value
                  specified with **priority** , using the information stored in
                  the Differentiated Services Field of the IPv6/IPv4 header
                  (RFC2474).
    


* * *
# tc-csum

## NAME



           csum - checksum update action
    


## SYNOPSIS



           **tc**... **action csum** _UPDATE_
    
           _UPDATE_ := _TARGET_ [ _UPDATE_ ]
    
           _TARGET_ := { **ip4h** | **icmp** | **igmp** | **tcp** | **udp** | **udplite** | **sctp** |
                   _SWEETS_ }
    
           _SWEETS_ := { **and** | **or** | **+**}
    


## DESCRIPTION



           The **csum** action triggers checksum recalculation of specified
           packet headers. It is commonly used to fix incorrect checksums
           after the **pedit** action has modified the packet content.
    


## OPTIONS



           _TARGET_ Specify which headers to update: IPv4 header (**ip4h**), ICMP
                  header (**icmp**), IGMP header (**igmp**), TCP header (**tcp**), UDP
                  header (**udp**), UDPLite header (**udplite**) or SCTP header
                  (**sctp**).
    
           **SWEETS** These are merely syntactic sugar and ignored internally.
    


## EXAMPLES



           The following performs stateless NAT for incoming packets from
           192.0.2.100 to new destination 198.51.100.1. Assuming these are
           UDP packets, both IP and UDP checksums have to be recalculated:
    
                  # tc qdisc add dev eth0 ingress handle ffff:
                  # tc filter add dev eth0 prio 1 protocol ip parent ffff: \
                       u32 match ip src 192.0.2.100/32 flowid :1 \
                       action pedit munge ip dst set 198.51.100.1 pipe \
                       csum ip and udp
    


* * *