The docker shell syntax (which is just a string as the RUN, ENTRYPOINT, and CMD) will run that string as the parameter to /bin/sh -c. This gives you a shell to expand variables, sub commands, piping output, chaining commands together, and other shell conveniences. RUN ls * | grep $trigger_filename || echo file missing && … Read more
Accrding to: http://www.vias.org/linux-knowhow/bbg_sect_08_02_01.html : -r If this option is given, backslash does not act as an escape character. The backslash is considered to be part of the line. In particular, a backslash-newline pair may not be used as a line continuation. It works on my machine. $ echo ‘\&|’ | while read -r in; do … Read more
You shouldn’t use ls like that and a for loop is not appropriate either. Also, the destination directory should be outside the source directory. mkdir /path/to/destination find . -type f -exec iconv -f iso-8859-1 -t utf-8 “{}” -o /path/to/destination/”{}” \; No need for a loop. The -type f option includes files and excludes directories. Edit: … Read more
For simple input, like two prompts and two corresponding fixed responses, you could also use a “here document”, the syntax of which looks like this: test.sh <<! y pasword ! The << prefixes a pattern, in this case ‘!’. Everything up to a line beginning with that pattern is interpreted as standard input. This approach … Read more
With NGINX Docker image Apply envsubst on template of the configuration file at container start. envsubst is included in official NGINX docker images. Environment variable is referenced in a form $VARIABLE or ${VARIABLE}. nginx.conf.template: user nginx; worker_processes 1; error_log /var/log/nginx/error.log warn; pid /var/run/nginx.pid; events { worker_connections 1024; } http { server { listen 80; location … Read more
First of all, the easiest way to run things at startup is to add them to the file /etc/rc.local. Another simple way is to use @reboot in your crontab. Read the cron manpage for details. However, if you want to do things properly, in addition to adding a script to /etc/init.d you need to tell … Read more
printf ‘\x31\xc0\xc3′ | dd of=test_blob bs=1 seek=100 count=3 conv=notrunc dd arguments: of | file to patch bs | 1 byte at a time please seek | go to position 100 (decimal) conv=notrunc | don’t truncate the output after the edit (which dd does by default) One Josh looking out for another 😉
If you wanted to remove a certain NUMBER of path components, you should use cut with -d”https://stackoverflow.com/”. For example, if path=/home/dude/some/deepish/dir: To remove the first two components: # (Add 2 to the number of components to remove to get the value to pass to -f) echo $path | cut -d”https://stackoverflow.com/” -f4- # output: # some/deepish/dir … Read more
Using –fail will make the exit status nonzero on a failed request. Using –head will avoid downloading the file contents, since we don’t need it for this check. Using –silent will avoid status or errors from being emitted by the check itself. if curl –output /dev/null –silent –head –fail “$url”; then echo “URL exists: $url” … Read more
You can use multiple –include flags. This works for me: grep -r –include=*.html –include=*.php –include=*.htm “pattern” /some/path/ However, you can do as Deruijter suggested. This works for me: grep -r –include=*.{html,php,htm} “pattern” /some/path/ Don’t forget that you can use find and xargs for this sort of thing too: find /some/path/ -name “*.htm*” -or -name “*.php” … Read more