Commands using export (101)

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combine `mkdir foo && cd foo` into a single function `mcd foo`
I find that I create a directory and then cd into that directory quite often. I found this little function on the internets somewhere and thought I'd share it. Just copy-paste it into you ~/.bash_profile and then `source ~/.bash_profile`.

List the biggest accessible files/dirs in current directory, sorted

Display / view the contents of the manifest within a Java jar file
Displays the manifest within a jar file. Can use it to confirm version number, etc.

Create the signature base string required for a Twitter stream feed
This is the SECOND command in a set for five that are needed for a Twitter stream feed. This command creates variable "b", the so-called "base string" required for oauth in Twitter stream feed requests. (The 256 char limit prevents giving it a better name) We use five environment variables created by a previous step: id, k1, once, ts and k3. The five environment variables are created in a separate command, please see my other commands. For more information on the signature base string, see dev.twitter.com/apps, click on any app (or create a new one) and then go to the "OAuth Tool" tab.

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

"hidden" remote shell
opens a "hidden" remote shell (login will not appear in "last" for example). This is not really hidden, because the login will be shown in auth.log and the process is visible anyways. ssh -T = Disable pseudo-tty allocation. bash -i = interactive shell

rename / move Uppercase filenames to lowercase filenames current directory
move filename/rename filenames with Uppercase to lowercase in current directory

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Testing ftp server status
I must monitorize a couple of ftp servers every morning WITHOUT a port-scanner Instead of ftp'ing on 100 ftp servers manually to test their status I use this loop. It might be adaptable to other services, however it may require a 'logout' string instead of 'quit'. The file ftps.txt contains the full list of ftp servers to monitorize.

Search big files with long lines
This is a handy way to circumvent the "Maximum line length of 2048 exceeded" grep error. Once you have run the above command (or put it in your .bashrc), files can be searched using: $ lgrep search-string /file/to/search


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