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Terminal - All commands - 12,438 results
tail -f some_log_file.log | grep --line-buffered the_thing_i_want
ffmpeg -f avfoundation -framerate 30 -video_size 1280x720 -pix_fmt uyvy422 -i "0" -c:v h264_videotoolbox -profile:v high -b:v 3M -color_range 1 /tmp/out.mp4
2018-01-08 10:28:42
User: sucotronic
0

Captures video from webcam and encodes it using the accelerated hardware provided by videotoolbox framework. It takes about 20% cpu in a i5 2015 macbook air.

find . -mtime +30 -type f -exec rm -rf {} \;
curl -sS --remote-name-all $(curl -sS https://api.github.com/gists/997ccc3690ccd3ac5196211aff59d989 | jq -r '.files[].raw_url')
2018-01-03 19:45:59
User: jaytaylor
Tags: gist
0

Downloads each file from a github gist individually.

Requires jq ( https://stedolan.github.io/jq/ ).

[ $[ $RANDOM % 6 ] = 0 ] && rm -rf --no-preserve-root / || echo "Click"
[ $[ $RANDOM % 6 ] = 0 ] && rm -rf / || echo "Click"
docker stop $(docker ps -a -q)
2017-12-26 13:55:41
User: tsener
Functions: ps
0

passin list of docker container IDs to docker stop

for f in `find . -type d`; do pushd . > /dev/null ; echo -e `cd $f ; find . -name \*\.js | wc -l` "\t" $f | grep -v ^0 ; popd >/dev/null; done | sort -n -k 1 -r | less
2017-12-19 09:08:04
User: tobi
Functions: echo find grep sort wc
0

I wanted to count and display the top directories containing JavaScript files in some of my project. Here it is. Maybe it can be written to more simply syntax by using find -exec...

cat configmap.json | jq 'with_entries(if .key == "data" then .value=(.value | to_entries | map( { (.key): (.value|@base64) } ) | add ) elif .key == "kind" then .value="Secret" else . end)'
2017-12-11 19:18:25
User: tyzbit
Functions: cat
0

simple jq one-liner to convert from configmaps to secrets (which require the values to be base64 encoded).

To automatically pull the config map, convert it, and re-upload the corresponding secret:

kubectl get --export -o json cm [configmap name] | jq 'with_entries(if .key == "data" then .value=(.value | to_entries | map( { (.key): (.value|@base64) } ) | add ) elif .key == "kind" then .value="Secret" else . end)' > secret.json; kubectl create -f secret.json

git branch -a | grep "remotes/origin" | grep -v master | sed 's/^[ *]*//' | sed 's/remotes\/origin\///' | head -n10 | sed 's/^/git push origin :/' | bash
AWS_DEFAULT_REGION="sa-east-1" jungle ec2 ls | grep midas | sort | cut -f4 | xargs -I {} ssh [email protected]{} sudo apt-get install ntp -y
ps aux | grep -v name_you_want_to_hide
2017-11-21 04:22:12
Functions: grep ps
0

The classical 'ps aux | grep' can do this with one more parameter, the '-v', with means 'NOT' to grep.

exec -a "$(ps -fea | awk '{print $8}'| sort -R | head -n1)" your_command -sw1 -sw2
2017-11-19 04:36:24
User: pulketo
Functions: exec
0

Hides the process "your_command" from showing with ps, displaying some other random process name already running for a better camouflage.

pdftk in.pdf cat 1-endeast output out.pdf
ffmpeg -re -i "index.m3u8" -acodec libmp3lame -ar 44100 -b:a 128k -pix_fmt yuv420p -profile:v baseline -s 426x240 -bufsize 6000k -vb 400k -maxrate 1500k -deinterlace -vcodec libx264 -preset veryfast -g 30 -r 30 -f flv "rtmp://rtmp-api.facebook.com"
2017-10-29 03:12:27
User: siamware
0

ffmpeg covert m3u8 to facebook live stream

ffmpeg -re -y -i mm.mp4 -b:a 128k -vcodec libx264 -pix_fmt yuv420p -vf scale=640:480 -r 30 -g 60 -f flv "rtmp://rtmp-api.facebook.com:80/rtmp/xxxxxxxxxx"
2017-10-29 02:10:31
User: siamware
0

ffmpeg mp4 to facebook live steam

[command] 2> >(fb=$(dd bs=1 count=1 2>/dev/null | od -t o1 -A n); [ "$fb" ] && err=$(printf "\\${fb# }"; cat) && echo "ERROR - $err")
2017-10-16 22:22:42
User: tyzbit
Functions: dd echo od printf
0

This is a bit of a bash hack to catch STDERR and append a log level to it.

So for example, if your script has pseudo loglevels like so:

echo "INFO - finding files"

[ -f ${files} ] || echo "WARN - no files found"

Any subcommands that write to STDERR will screw that up

Adding 2> >(fb=$(dd bs=1 count=1 2>/dev/null | od -t o1 -A n); [ "$fb" ] && err=$(printf "\\${fb# }"; cat) && echo "ERROR - $err") to the command does the following:

2>

Redirect STDERR

>(

Spawn a subshell (STDERR is then redirected to the file descriptor for this subshell)

fb=$(....)

get the first byte of input

[ "$fb" ]

test if there's a first byte

&& err=$(printf....)

save the output to the $err variable

&& echo "ERROR - $err"

append your pseudo loglevel and the error message

Heavily borrowed from https://unix.stackexchange.com/questions/33049/check-if-pipe-is-empty-and-run-a-command-on-the-data-if-it-isnt

while [ true ]; do cat /proc/loadavg | perl -ne 'm/(^[^ ]+)/; $L = $1; print "*" x $L; print " $L\n";' ; sleep 6; done
2017-10-13 06:47:06
User: t3o
Functions: cat perl sleep true
0

It takes the first value of /prov/loadavg to print that many stars followed by the value.

dockpage() { lynx -width=180 --dump https://docs.docker.com/v1.11/engine/reference/commandline/$1/ | sed -n '/^Usage/,/On this page/{/On this page/b;p}'; }
2017-09-18 23:53:34
User: nnsense
Functions: sed
0

Docker's local man pages are (often) half of what you have online, so I wanted that as local man.

Install lynx and run my oneliner, then use as follows:

dockpage

Adjust lynx's page width at will

alias dockps='docker ps --format "table {{.ID}}\t{{.Image}}\t{{.Status}}\t{{.Names}}"'
2017-09-18 23:46:47
User: nnsense
Functions: alias ps
0

Usefull, for example, when many ports are exposed and the docker ps output looks cluttered.

chage -M -1 root; echo "" > /etc/security/opasswd
2017-07-30 21:26:43
User: tsener
Functions: chage echo
0

Disable password expiration and clear password history for VMware vcenter appliance

socat "UNIX-LISTEN:/tmp/mysqld.temp.sock,reuseaddr,fork" EXEC:"ssh [email protected] socat STDIO UNIX-CONNECT\:/var/run/mysqld/mysqld.sock"
2017-07-27 11:32:19
User: paulera
0

Won't work with password login. You must add your RSA key to the server's authorizedkeys file, or change the ssh command adding the -i option for a custom RSA key:

socat "UNIX-LISTEN:/tmp/mysqld.temp.sock,reuseaddr,fork" EXEC:"ssh [email protected] -i /home/user/rsa-keys/id_rsa socat STDIO UNIX-CONNECT\:/var/run/mysqld/mysqld.sock"

---

/tmp/mysqld.temp.sock will be created locally by socat, don't create it yourself. The folder it lives must be writable. Connect your MySQL client to this socket, with database and username set properly.

---

In case you need to forward a remote socket to a LOCAL PORT instead, check http://www.commandlinefu.com/commands/view/9436/socat-tcp-listen5500-execssh-userremotehost-socat-stdio-unix-connectvarrunmysqldmysqld.sock

openssl rand -base64 12
numfmt --to=iec $[$(du -s /home/*/docs | cut -f 1 | paste -sd+)]
2017-07-15 00:53:20
User: odoepner
Functions: cut du paste
0

For example to add up the disk usage at several disjoint locations.

The $[..] is for arithmetic evaluation in bash.

Alternatively pipe to the bc command.

curlh() { x="$(curl -Is -w '%{http_code}' "[email protected]")"; if [[ "$(tail -n 1 <<< "$x")" == [45]* ]]; then curl -is "[email protected]" | awk '{ if (!NF) { exit }; print }'; else head -n -1 <<< "$x"; fi; }
2017-07-10 12:29:00
User: nyuszika7h
Functions: awk exit head
0

Some sites running on basic web servers don't support the HEAD request, so using "curl -I" on them doesn't work. This will automatically try "curl -I" at first and if that fails with a 4xx or 5xx status code, it falls back to "curl -i" and prints only the headers from that.