What does ` (backquote/backtick) mean in commands?
5. The backtick ` runs the contents of the enclosed string, so something like this. will find out the path to the hostname command, and then tell you how it was built. The command that you put in your question runs id -u to get the effective user id, and …
bash - Understanding backtick (`) - Unix & Linux Stack Exchange
Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.
Awesome symbols and characters in a bash prompt
Feb 7, 2018 · If you want to avoid non-ASCII characters to make your .bashrc resilient to file encoding changes, you'll need to enter the bytes corresponding to these characters in the UTF-8 encoding. You can see the hexidecimal values by running echo ∴ → ☿ ★ | hexdump -C in a UTF-8 terminal, e.g. ∴ is encoded by \xe2\x88\xb4 in UTF-8.
How can the link target of /dev/rtc be changed?
Dec 1, 2015 · Start the service: #>systemctl start rtc.service. You may check if the /dev/rtc* devices have changed accordingly using ls -lah /dev/rtc* you should have something like this: lrwxrwxrwx 1 root root 4 Apr 3 18:19 /dev/rtc -> rtc1. lrwxrwxrwx 1 root root 4 Apr 3 18:19 /dev/rtc0 …
How can I monitor disk io? - Unix & Linux Stack Exchange
Using the Debian package, you must enable the stat collector via the /etc/default/sysstat config file after package installation. To see current utilization broken out by device, you can use the iostat command, also from the sysstat package: $ iostat -x 1. Linux 3.5.2-x86_64-linode26 (linode) 11/08/2012 _x86_64_ (4 CPU) avg-cpu: %user %nice ...
tput setaf color table? How to determine color codes?
Mar 12, 2016 · Color #define Value RGB black COLOR_BLACK 0 0, 0, 0 red COLOR_RED 1 max,0,0 green COLOR_GREEN 2 0,max,0 yellow COLOR_YELLOW 3 max,max,0 blue COLOR_BLUE 4 0,0,max magenta COLOR_MAGENTA 5 max,0,max cyan COLOR_CYAN 6 0,max,max white COLOR_WHITE 7 max,max,max
Check if terminal supports 24-bit / true color - linux
Jun 18, 2018 · Not a direct answer, but if you're OK with falling back to less granular colour, you can just print the 256-color escape code immediately before the 24-bit code (e.g. \e[48;5;124m\e[48;2;65;0;0m for a red background). Terminals that don't support 24-bit colour will ignore the second escape code and use the less-precise colour from the palette ...
How to use variables inside single quotes
Jan 10, 2015 · I have an application which takes as an input attributes in double quotes embedded in single quotes. Take for example this right command: command -p 'cluster="cl1"' In order to automate it, I cre...
How does the Linux kernel handle shared IRQs?
When a PCI¹ hardware device raises the IRQ line, the kernel's low-level interrupt handler is called, and it in turn calls all of the registered interrupt handlers, passing each back the dev_id you used to register the handler via request_irq(). The dev_id value needs to be machine-unique. The common way to do that is to pass a pointer to the ...
How can I grep for this or that (2 things) in a file?
Note: Shell script lines are used directly. Typed input-lines are first history-expanded. Each bash line is first tokenized, or in other words chopped into what are called tokens.