Use the lsb_release -a command to display the Ubuntu version.

Your "driver" (wrapper, really) script

if [ "$#" -eq 0 ]; then cat else printf '%s\n' "$@" fi |

The lonesome cat isn’t useless.  UUOCs are typically characterized by having exactly one filename argument; this one has none.  It connects the input to the function (which is the input of the if statement) to the output of the if statement (which is the input to the base64 –decode statement)

You can pre-seed your less pager with a search pattern so that you can move between files with n/N keys: [pager] diff = diff-so-fancy | less --tabs=4 -RFXS --pattern '^(Date|added|deleted|modified): '

Try adding \ before your ls, e.g.: \ls | xargs file.

The ls command doesn't expand wildcards, it's the shell that does. Do not parse the output of ls, it's practically never needed and often breaks something.

DO NOT PARSE LS.

wrapper script for mysqldump

a shell wrapper for ffmpeg

--ignore-unmerged When restoring files on the working tree from the index, do not abort the operation if there are unmerged entries and neither --ours, --theirs, --merge or --conflict is specified. Unmerged paths on the working tree are left alone. Holy smokes! I guess the git-ish fix for the user interface problem here will be to rename the option from --ignore-unmerged to --ignore-unmerged-except-in-cases-where-we-do-not-want-to-allow-that--consult-documentation-then-source-code-then-team-of-gurus-when-you-cannot-figure-it-out---and-wait-while-half-of-them-argue-about-why-it-is-right-as-is-while-the-other-half-advocate-adding-four-more-options-as-the-fix.

This buildpack installs shims that always add --headless, --disable-gpu, --no-sandbox, and --remote-debugging-port=9222 to any google-chrome command as you'll have trouble running Chrome on a Heroku dyno otherwise.

find . -regextype posix-extended -regex ".*\.(jpg|gif|png|jpeg)"

That's an important remark. find /path/to/ -iname '*.gif' -o -iname '*.jpg' -print0 will only print the jpg files! You need brackets here: find /path/to/ \( -iname '*.gif' -o -iname '*.jpg' \) -print0

And get a list of characters in a font like this:

Shims are just tiny wrappers created by asdf that just forward execution to the real versioned executables installed by asdf. This way, asdf has a single shims directory added to your PATH and has no need of mangling the PATH for every installed version.

Always use a while read construct: find . -name "*.txt" -print0 | while read -d $'\0' file do …code using "$file" done The loop will execute while the find command is executing. Plus, this command will work even if a file name is returned with whitespace in it. And, you won't overflow your command line buffer.

So the correct command to use is findmnt, which is itself part of the util-linux package and, according to the manual: is able to search in /etc/fstab, /etc/mtab or /proc/self/mountinfo

When running Windows on your Mac via Boot Camp, the keyboard mappings are changed so they make more sense in Windows. The Option key functions as Alt and the Command key functions as the Windows key.

SETEX key seconds value

type

Suddenly we’d come full circle. The fastest way to launch programs was to type their name into a box, only a box that looked a bit more stylish than the terminal of old.

flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepoflatpak install flathub org.chromium.Chromium

I think it's very confusing to overload common executables, such as yarn, in the /bin directory as I often put that bin directory first in my path. Thus, I'd unexpectedly get the bin/yarn rather than my system yarn, which I manage with yvm.

fzf --preview 'bat --style=numbers --color=always --line-range :500 {}'

unbuffer connects to a command via a pseudo-terminal (pty), which makes the system treat it as an interactive process, therefore not using any stdout buffering.


unbuffer disables the output buffering that occurs when program output is redirected. For example, suppose you are watching the output from a fifo by running it through od and then more.    od -c /tmp/fifo | more You will not see anything until a full page of output has been produced. You can disable this automatic buffering as follows:    unbuffer od -c /tmp/fifo | more

Today, many users rely upon graphical user interfaces and menu-driven interactions. However, some programming and maintenance tasks may not have a graphical user interface and may still use a command line.

empty is an utility that provides an interface to execute and/or interact with processes under pseudo-terminal sessions (PTYs). This tool is definitely useful in programming of shell scripts designed to communicate with interactive programs like telnet, ssh, ftp, etc.

If there are some pipe between these commands, you need to flush stdout. for example: script -q /dev/null commands... | ruby -ne 'print "....\n";STDOUT.flush'

Job control is what happens when you press ^Z to suspend a program, or when you start a program in the background using &

The command also can be run in silent mode (tty -s) where no output is produced, and the command exits with an appropriate exit status.

Quite a lot of programs actually detect if their output goes to a file (e.g. try man | grep -F a and you will not be able to scroll back and forth).

sed can do so much more, but is totally overkill for this. tr is the right tool for THIS job, but knowledge of sed and regexes will certainly come in handy later!

Given the deskopen script, you can use a reference to it as the shebang line in a .desktop file

this is so stupid (that there is no sensible way to run a Desktop file from the terminal)

gtk-launch <app-name> - where <app-name> is the file name of the .desktop file, with or without the .desktop extension.

I find it convenient to change proxy and other settings through gui window by right-clicking on launcher icon on my desktop. I mostly start slack by clicking desktop launcher, but also want to be able to start it from command line in some cases.

If you really want this, I suggest you write a little function that extracts the executable name from the .desktop file and runs it. Add these lines to your shell's initialization file (e.g. ~/.bashrc): runDesktop () { eval "$(awk -F= '$1=="Exec"{$1=""; print}' "$1")" } Then, you can run your .desktop file with runDesktop ~/Desktop/slack.desktop

We could add heuristics like: is the file inside XDG_DATA_DIRS/applications? if not, is the file inside XDG_DATA_HOME/applications? if not, is the file marked as executable? if not, open with the text editor

Hello , since I made a modification in gio-tool (#2098 (closed)) , I seen this issue and decide to give it go. I implemented an unix only solution only for launching a desktop file through gio command, see !1779 (merged)

When one is searching for it on the internet, there are many many people wondering how one can open .desktop files. It seems trivial, since one usually just has to click an item on the launcher so one thinks there must be some way.

I have to agree with Raphael here that this should probably be handled in gnome-open, its a pain to have to implement .desktop parsing code in every beagle front end when I can't really think of an instance where the expected behavior wouldn't be to execute the associated command.

I don't know what nautilus does, but i think when you double click a .desktop file it launches the associated program, i guess they don't use gnome-open then..

deskbar should probably detect their extension and execute the relevant command as opposed to opening the file for editing.

Is somehow possible to run a "Desktop Entry" from another "Desktop Entry"?

For example, on the terminal I'm using, the right arrow outputs ^[[C. You can see what sequence your terminal outputs by pressing Ctrl-V Right Arrow. The same is true for other cursor-control keys such as Page Up and End.

As usual with almost any command, if you want a normal argument that starts with a - to not be interpreted as a switch, precede it with --

it propagates (Option -p) the returnlevel ($?) so you may use it for your purpose.

It's an implementation of the command pattern in Ruby.

Uses

The central ideas of this design pattern closely mirror the semantics of first-class functions and higher-order functions in functional programming languages. Specifically, the invoker object is a higher-order function of which the command object is a first-class argument.

rsync --info=progress2

As of OpenSSL 1.1.1, providing subjectAltName directly on command line becomes much easier, with the introduction of the -addext flag to openssl req

I debugged docker-compose and docker-py and figured out that you should either use environment variables or options in command. You should not mix these . If you even specify --tls in command then you will have to specify all the options as the TLSConfig object, as now TLSConfig object is created completely from the command options and operide the TFSConfig object created from the environment variable.

xargs -0 cp -t ~/foo/bar

Speed example -- over 829 files, the "find -exec" method took 26 seconds while the "find -print0 | xargs --null" method tool 0.7 seconds. Significant difference.

Sadly, bash can't handle long options which would be more readable, i.e.:

To get a feel for how much pseudo-random data is available in your entropy pool, you can run this command:$ cat /proc/sys/kernel/random/entropy_avail 2684 The number shown appears to represent the number of bits of entropy that have been collected. Even 2,684 might not seem like much in a world in which we routinely speak in terms of terrabytes, but numbers above 100 are said to be a good sign. I

Write programs to handle text streams, because that is a universal interface.

The gem provides a command line utility for checking passwords.

I had never considered it that in nearly a decade of using GNU find! Thank you for that! It will definitely change the way I think about -prune from now on.

I think this structure is much easier and correlates to the right approach

it isn't actually -prune itself that causes this, by the way. The issue is that the or operator "short-circuits", and or has lower precedence than and. The end result is that if a file called .snapshot is encountered it will match the first -name, -prune will then do nothing (but return true), and then the or returns true since its left-argument was true. The action (eg: -print) is part of its second argument, so it never has a chance to execute.

If all you want to do is print the results you might be used to leaving out the -print action. You generally don't want to do that when using -prune.

which means that it'll also print out the name of the directory you're pruning, which usually isn't what you want. Instead it's better to explicitly specify the -print action if that's what you want

The thing I'd found confusing about -prune is that it's an action (like -print), not a test (like -name). It alters the "to-do" list, but always returns true.

Did you expect the temp directory to get printed? In the last example, we saw the directories ./temp and ./C/temp got printed, but not now. This is the effect of the -print option. By default, the find command prints all the files matching the criteria. However, once the -print option is specified, it will print files only on explicit print instructions. In this find command, -print is associated in the other side of the OR condition, and hence nothing will get printed from the 1st part of the condition.

12. Same using the wholename option and prune to exclude directory: $ find . -wholename "./temp" -prune -o -perm 644 -print ./area.pm ./C/temp ./C/f2.c find has a switch with the name 'wholename'. Say, in your directory tree, there might be more than one temp directory. The earlier approaches will prune all the temp dierctories. In case, if the requirement is to prune a specific temp directory, then you can give the path of the directory itself. Note: The path specified in the wholename option should be relative to the search path specified, not the absolute path. 

Write a wrapper script that sets the LD_LIBRARY_PATH environment variable.

Through a process called rehashing, rbenv maintains shims

Shims are lightweight executables that simply pass your command along to rbenv.

An ssh public key in a ~/.ssh/authorized_keys file can have a command="" option which forces a particular command to be executed when the key is used to authenticate an ssh connection. This is a security control that mitigates against private key compromise. This is great when you only need to execute a single command. But if you need to perform multiple tasks, you would normally need to create and install a separate key pair for each command, or just not bother making use of forced commands and allow the key to be used to execute any command.

from="<ip>",command="/usr/local/sbin/validate-rsync" ssh-dss AAAAZ5Hbl......

echo "from="${MYIP%% *}",no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty,command="rsync ${SSH_ORIGINAL_COMMAND#* }" $(ssh-keygen -yf ~/.ssh/rsync_rsa)" | ssh targetserver "cat - >>~/.ssh/authorized_keys" Note that the ‘command=’ restriction (http://larstobi.blogspot.ch/2011/01/restrict-ssh-access-to-one-command-but.html) will not apply if ‘/etc/sshd_config’ has already a ‘ForceCommand’ directive.

GitHub Packages uses the native package tooling commands you're already familiar with to publish and install package versions.

Using find and cpio is a more unix-y approach in that you let find do the file selection with all the power that it has, and let cpio do the archiving. It is worth learning this simple use of cpio, as you find it easy to solve problems you bang your ahead against when trying tar.

find

From the man pages The environment variables can be specified in lower case or upper case. The lower case version has precedence. http_proxy is an exception as it is only available in lower case. Using an environment variable to set the proxy has the same effect as using the --proxy option

when you ask the same people to do something FOR you, e.g. lend you a book or sign a recommendation letter for you, you can’t just use ください.

In Bash you quite often need to check to see if a variable has been set or has a value other than an empty string. This can be done using the -n or -z string comparison operators.

Every time a customer service assistant shrugs and says “computer says no” or an organization acts in crazy, inflexible ways, odds-are there’s a database underneath which has a limited, rigid view of reality and it’s simply too expensive to fix the software to make the organization more intelligent. We live in these boxes, as pervasive as oxygen, and as inflexible as punched cards.

If you have a copy of the ReSpec repository handy, you may see that there is also a respec2html.js tool under tools/. Feel free to try using it instead of the above process, but please note that it is not used much currently and may behave in a somewhat experimental manner (experiences with it vary — but it's worth a shot if you're looking for a way to generate ReSpec output from the command line).

Infrastructures, for Collier, are amixture of political rationality, administrative techniques, and material systems, and his interest isnot in infrastructure per se but in what it tells us about practices of government. Soviet electricityprovision, through this lens, is analyzed for how it reveals a system of total planning in a commandeconomy rather than for what it tells us about the effects of electricity on users in Russia.

What, then, are the requisites of a good general and what ability do they involve?