Tag Archives: shell

Shell: repeat a task multiple time

All shells (bash/zsh):

watch -n 3 "curl --location --request GET 'http://...'"

1	watch -n 3 "curl --location --request GET 'http://...'"

will run curl every 3 seconds until you break it. zsh specific:

repeat 5 { curl --location --request GET 'http://...' }

1	repeat 5 { curl --location --request GET 'http://...' }

will repeat it 5 times without any delay

Interesting alternative to grpc_cli

https://github.com/ktr0731/evans It has REPL mode and CLI mode for e2e tests I think, it could be a good alternative to grpc_cli.

Pipeline view in shell

tail -f /var/log/nginx/access.log | pv --line-mode --rate > /dev/null

1	tail -f /var/log/nginx/access.log \| pv --line-mode --rate > /dev/null

https://serverfault.com/questions/473905/is-there-a-unix-linux-command-to-count-lines-per-second-from-stdin

grep, zgrep, less and zless regexp examples

Grep all files with mask:

grep "regex to find" /var/log/lb-*.net/nginx/error.log

1	grep "regex to find" /var/log/lb-*.net/nginx/error.log

Grep all zipped files with mask:

zgrep "regex to find"  /var/remote-log/nodejs-1*.net/node/error.log.*

1	zgrep "regex to find" /var/remote-log/nodejs-1.net/node/error.log.

Less all files with mask:

less /var/log/lb-*.net/nginx/error.log

1	less /var/log/lb-*.net/nginx/error.log

Grep all zipped files with mask:

zless  /var/remote-log/nodejs-1*.net/node/error.log.*

1	zless /var/remote-log/nodejs-1.net/node/error.log.

Tail all files with mask:

tail -f /var/log/lb-*.net/nginx/error.log

1	tail -f /var/log/lb-*.net/nginx/error.log

Search for occurencies in directory with grep

grep -rnw '/path/to/somewhere/' -e 'pattern'

1	grep -rnw '/path/to/somewhere/' -e 'pattern'

https://stackoverflow.com/questions/16956810/how-do-i-find-all-files-containing-specific-text-on-linux

How to count resource usage in linux

ps -eo pid,ppid,cmd,%mem,%cpu --sort=-%mem | head -n 5

1	ps -eo pid,ppid,cmd,%mem,%cpu --sort=-%mem \| head -n 5

It will output something like this:

PID  	PPID 	CMD                      	%MEM 	%CPU
2591	2113 	/usr/lib/firefox/firefox    7.3 	43.5
2549   2520 	/usr/lib/virtualbox/Virtual 3.4  	8.2
2288       1 	/home/gacanepa/.dropbox-dis	1.4	0.3
1889   1543	c:\TeamViewer\TeamViewer.ex	1.0	0.2
2113	1801	/usr/bin/cinnamon		0.9	3.5

PID PPID CMD %MEM %CPU

2591 2113 /usr/lib/firefox/firefox 7.3 43.5

2549 2520 /usr/lib/virtualbox/Virtual 3.4 8.2

2288 1 /home/gacanepa/.dropbox-dis 1.4 0.3

1889 1543 c:\TeamViewer\TeamViewer.ex 1.0 0.2

2113 1801 /usr/bin/cinnamon 0.9 3.5

grep по файлам в директории

grep -nr 'yourString*' ./your/dir

1	grep -nr 'yourString*' ./your/dir

http://stackoverflow.com/questions/4121803/how-can-i-use-grep-to-find-a-word-inside-a-folder

Настройки клавиатуры в iTerm

Чтобы включить нормальные перемещения по словам и тп: Go to iTerm Preferences → Profiles, select your profile, then the Keys tab. Click Load Preset… and choose Natural Text Editing.

Более быстрое обновление пакетов yum

У нас деплой производится rpm-пакетами на CentOS командой

sudo yum install [пакет]

1	sudo yum install [пакет]

При этом часто пишется, что нового пакета нет, хотя он точно есть, просто проверка репозитория производится не каждый раз. Чтобы заставить машину сначала проверить репозитории, нужно выполнить следующее:

sudo yum clean rpmdb
sudo yum install [пакет]

1 2	sudo yum clean rpmdb sudo yum install [пакет]

http://yum.baseurl.org/wiki/YumCommands или

yum makecache
sudo yum install [пакет]

1 2	yum makecache sudo yum install [пакет]

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Deployment_Guide/sec-Working_with_Yum_Cache.html

Git: посмотреть последние merge веток

git log -n50 | grep Merge

1	git log -n50 \| grep Merge