Check These Out
I often deal with long file names and the 'ls -l' command leaves very little room for file names. An alternative is to use the -h -o and -g flags (or together, -hog).
* The -h flag produces human-readable file size (e.g. 91K instead of 92728)
* The -o suppresses the owner column
* The -g suppresses the group column
Since I use to alias ll='ls -l', I now do alias ll='ls -hog'
Useful for checking if there are differences between last and penultimate command.
I learned a few things reading this command. But I did run into a few issues:
1. On systems that don't use GNU echo (e.g. macOS 10.14.5 Mojave), the e option may not be supported. In this case ANSI escape codes will echoed as text and the terminal will not flash, like this:
\e[?5h\e[38;5;1m A L E R T Thu Jun 20 16:31:29 PDT 2019
2. Since the read command strips\ignores leading backslashes, if a user types the backslash character once in the loop, it will not break. Typing backslash twice in a loop will break as expected.
3. The foreground color is set to red (\e[38;5;1m) on every loop. This could be set once before we call while, and then reset once when the loop breaks.
4. Instead of resetting the foreground color when it breaks, the video mode is set back to normal (\e[?5l). This has the effect of leaving the terminal text red until it is manually reset.
The alternative I'm proposing here addresses these issues. I tested it on macOS and Arch Linux.
As of 10.04 LTS, you need to use this command-line to reports bugs to the launchpad.net tracking system (you need a launchpad acct for this to work). This command is preferred over using the website because it collects/sends info about your system to help developers.
ubuntu-bug is a symlink to apport-bug which sees if KDE/Gnome is running and calls apport-gtk/apport-kde dialogs, otherwise apport-cli, so you can fill out a bug report.
First run 'ubuntu-bug' without args to see a list of known symptoms. If there's no matching symptom, or you know which package is to blame, then run 'ubuntu-bug <package>'. If the process is still running, use 'ubuntu-bug <PID>'
I had a hard time in finding the correct settings to get reasonable output from a coin selector which sends its data over a serial line. In the end, minicom came to the rescue and pointed me on the right track.
So, if you need to do something similar, these settings may help you.
Replace ttyUSB0 with your device file, 9600 with your baud rate, 5 with your read timeout (10ths of a second), and 1 with the minimum numbers of characters you want to read.
You can then open the device file like you are used to do, example:
$ DATA="`xxd -ps -l 5 \"$DEV\"`"
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"
}
Create an AES256 encrypted and compressed tar archive.
User is prompted to enter the password.
Decrypt with:
$ openssl enc -d -aes256 -in | tar --extract --file - --gzip
Uses logger in a while loop to log memory statistics frequently into the local syslog server.
Shows all block devices in a tree with descruptions of what they are.
