When I was learning Unix in the early nineties I struggled to understand and remember the syntax of commandline tools. To help myself learn, each time I discovered a new command, I’d record each new success so I had a known good starting point for the next time.
Initially I kept these notes in ~/etc/ so they were easy to grep.
Later they moved to a wiki page where they continued to flourish, and then finally to my
WordPress site where they languished … until (hopefully) now!
Over the years I've kept the habit because it continues to be useful.
101 Recently Updated Gists
Zip the list of files that come from
stdin.Print headers and contents of whoami.spack.org to standard out, but follow and show any redirects.
Finds SUID/GUID files
Checks (but does not retrieve or delete) messages for
larry@alaska.net (-k keeps on server)Finds
a.out executablesSame as above only bind as
uid=adam and prompt for the password (-w <password> to specify on the command line)Boot from USB stick via Grub (details).
Un-rot13 a message, and it works in pine if you enable the
| commandCase-insensitive searching with
gawk by setting builtin variable.Start up OpenLDAP pointing explicitly to the config file and setting debugging to my preferred setting.
Renames all files listed to YYYY-MM-DD_HH-MM-SS (where date is when the picture was taken via EXIF data).
Provides a top-like view of network traffic. Shows only TCP traffic on WiFi interfaces from processes named
java or httpd.Use the
time command to see how long a process takes to run. Output is formatted by the TIME variable (long format elapsed time). Details here.Generate a list of all 1Password groups and the vaults which they are mapped to.
Upgrade Debian
Resize the filesystem
/data (/dev/xvda3) to a larger than 32bit filesystem. Note the first resize2fs only converts to a 64 bits, the second actually resizes the filesystem.Add to `.zshrc` to automatically start a tmux session on login. If there is an existing session, it will attach, otherwise it'll spawn a new tmux session.
Zsh trick for checking to see if a command exists without spawning a shell.
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similar to stunnel command, much more verbose
shows which ntp servers you are connected to
To get better font rendering on Linux, disable hinting and subpixel rendering, and enable stem darkening by adding this to your
/etc/environment file.Set awk field delimiter to use a character class (be either <space> or <period>).
LILO: To get to root without the root password
Use
sftp to connect to leia.spack.org using gateway.spack.org as a jump host.Download an archiveable copy of a website using
wget.Dumps the structure of the
drupal database to drupal.sql.New tool built into macOS 12 (Monterey) to test quality of internet connection (some details at danpetrov.xyz). #speedtest
Take a screenshot of a website (details).
Converts the IP 10.0.2.254 into hex.
Add to your
~/.zshrc and then you can search these gists from the shell with: gists <keyword>Download the file and keep the file if the transfer gets interrupted allowing it to be resumed where it left off.
sets up stunnel to map ssl traffic coming into 995 to the local pop port unencrypted.
Shows temp and stuff
How to clone a repo and then take it back to a specific branch.
Watch for traffic to
192.168.1.1 on ports 110 or 143 which start with “user” or contain “login”.Create thumbnail page with four images per column, omitting image count in caption, using captions and creating “web sized” images for display in slide page.
Look up TXT records for spack.org using DNS-over-TLS from the DNS server dns.spack.org.
Update UFW firewall to allow all TCP traffic to ports 80, 443 and 8080-8090 inclusive and adds a comment for the rule.
Bash function (eg. for
Usage: apt-cache –names-only search redis | flaunt ^redis
~/.bash_profile) to highlight any matching text. Usage: apt-cache –names-only search redis | flaunt ^redis
List all local snapshots and then delete them.
Flushes the local DNS cache (useful if you’ve changed mail server IP addresses or something)
Retry a command 5 times, waiting for 15 seconds before retrying.
Only replace
foo.txt with bar.txt if it's newer, and backup foo.txt to foo.txt~#~ before overwriting (where # is an ever incrementing number).blah
Broadcast a DHCP client request with a MAC address and see responses from all DHCP servers.
Use
awk to generate a list of usernames from a CSV list of full names by grepping the passwd file.View Caprover logs
Download the file to a local name which matches the remote name, and if the download is interupted figure out automatically the offset at which to resume.
Connect to
smtp.spack.org:587 and initiate an SMTP STARTTLS session. More OpenSSL examples here.Use the Bash builtin
time to see how long a process takes to run. Output is formatted with the TIMEFORMAT variable (3 decimal places, long format, Elapse time). Details here.Verbose output including disks, serial numbers, cpu’s etc.
tells all about the package.
List all APFS snapshots on local disk; delete a snapshot to free up space and mount a snapshot to recover files.
Show what package /usr/local/sbin/mtr belongs to.
Test NFS locking semantics.
Print the list of dates between
2010-01-01 and 2010-01-10 skipping weekends. Just part of the amazing dateutils package.(panther) Revert focus follow mouse back to normal off setting by deleting the change.
Search for the meaning of any OSX error code with 113 in it.
same as the host version
Python tool (domainaware/checkdmarc)for looking up DMARC and SPF record and showing any warnings.
useful for debugging
ntpCase-insensitive searching with awk by forcing $0 to lowercase.
Stuff
Reconfigure a Debian system to ask you any configuration a package may want to know (by default it only asks you important questions)
Remove all files which aren't managed by Git.
remove control characters from man output
How to only grep stderr without redirecting all of stderr to stdout. Can use “| tee 2> >(grep …)” on a command which doesn’t support redirection.
Split
blah.log into multiple gzip’d files each 1000 lines long.4 pg/pg to printer vger
Shows the status of currently running disk scrubs.
How to simulate
bash commandline arguments.Disable
.DS_Store and AppleDouble files on network and USB devices.Uses awk to rename all files and get rid of any capital letters.
As the user
www-data run the command php console.php files:scan –all on the container “nextcloud-app”.Disable’s linux screen saver
views a man page without man command
Create a RAM disk (
tmpfs) with a maximum size of 50MB and read/write only by root (default is mode 1777). See /usr/srcFix slow performance of macOS addressbook/contacts app. Only works for contacts stored locally, for CardDAV clients just remove contacts via
System Settings > Internet Accounts (source).gets enterprise mibs
Remove all falsy values (everything except 🍌).
Recursively copy the contents of WorkPace.app and the resource forks into a compressed CPIO archive.
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Clone a git repository into a non-empty directory (note that this overwrites exiting files).
Create an SSL certificate for mera using Cloudflare DNS challenge. Format of cloudflare.ini is described here. Requires installing
certbot and python3-certbot-dns-cloudflare packages in Ubuntu.Dumps the structure and the data of all databases to
mysql_all.sql (including all the MySql specific create commands)Resizes a directory full of images to thumbnail size suitable for incorporating into a “life poster” (see comment by Mark Pilgrim).
Convert Unix time to normal time.
Mailman page to modify individual subscriptions
Disable X11 starting on boot with GDM3 / systemd. Use
get-default to read current setting. To restore X11 use graphical.target.Download (if necessary) the
zabbix/zabbix-appliance:latest image and name it zabbix-appliance locally. Map container ports 10051/80 to 1051/81 respectively (so that external port 81 routes to internal container port 80)Put a <p> at the beginning of every paragraph
List all tags (versions) available for a Docker image at hub.docker.com.
Details of disks and volumes including failed disks, rebuiding disks and hot spares.
Lists all required software updates from the AppleOsx site. You can also use it to install the packages.
Takes standard in (from
echo in this case) and replaces all instances of foo with BAZ.Talk dirty to whois
installs onto the
/mnt mounted device using etc/lilo.conf as the source file.Use the BitWarden commandline to retrive an item and then
jq to only print the password. More information at ryan.himmelwright.net.(MacPorts) Upgrade subversion to the latest version (without “-u” the old version won’t be uninstalled automatically)
create and mount a ramdisk