Commands by lgarron

Commands by lgarron (10)

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Print macOS current power delivery max wattage

Print the max wattage of the current power draw source for a Mac. Note that the current amount of watts drawn may be lower, particularly if a high-wattage adapter is plugged into a Mac that has a full battery. Show Sample Output
This is sample output - yours may be different.
```
      Wattage (W): 140
```
0

system_profiler SPPowerDataType | grep Wattage

lgarron · 2023-07-06 17:58:00 202
Create a square thumbnail or favicon using ImageMagick

Resize `file.png` to a 32x32 px image. Use a value other than 32 to create other icon sizes (e.g. 16x16 or 32x32). Combine two favicon sizes using: `convert icon-16px.png icon-32px.png favicon.ico` For a social media preview image, use `2:1#` for the extent and `1200` for the scale.
This is sample output - yours may be different.
9

convert file.png -background transparent -gravity Center -extent 1:1# -scale 32 file-32px.png

lgarron · 2023-03-08 04:11:12 626
Delete a certificate from the macOS security keychain

Use `security list-keychains` to find possible keychains, and `security dump-keychain` to look for certificates. `sudo security delete-certificate` without arguments shows options for removing: by common name or by SHA-1 hash. This is especially useful if a certificate locks up Keychain Access.app, which happens for certificates with many SANs in macOS 10.12. Found via: http://stackoverflow.com/a/16019443
This is sample output - yours may be different.
0

sudo security delete-certificate -c 1000-sans.badssl.com

lgarron · 2017-04-06 01:40:04 21
Get the SAN (subjectAltName) of a site's certificate.

Based on http://stackoverflow.com/questions/13127352/checking-alternative-names-for-a-san-ssl-cert Replace "facebook.com" with the desired hostname. Show Sample Output
This is sample output - yours may be different.
```
depth=1 /C=US/O=DigiCert Inc/OU=www.digicert.com/CN=DigiCert High Assurance CA-3
verify error:num=20:unable to get local issuer certificate
verify return:0
DONE

*.facebook.com
facebook.com
*.fb.com
fb.com
*.fbsbx.com
*.fbcdn.net
*.xx.fbcdn.net
*.xy.fbcdn.net
*.xz.fbcdn.net
*.m.facebook.com
*.messenger.com
messenger.com
```
1

echo "quit" | openssl s_client -connect facebook.com:443 | openssl x509 -noout -text | grep "DNS:" | perl -pe "s/(, )?DNS:/\n/g"

lgarron · 2015-08-13 22:50:45 9
Change caps lock to backspace (Works on Ubuntu 14.04)

The internet is full of advice about how to change the caps lock key into a backspace key (a useful practice that originated with Colemak), but a lot of instructions are complicated or outdated. After *lots* of searching for something that still worked on Ubuntu 14.04, I finally found that this simple command is sufficient and takes effect immediately. (Found at: http://www.howtogeek.com/194705/how-to-disable-or-reassign-the-caps-lock-key-on-any-operating-system/ )
This is sample output - yours may be different.
0

setxkbmap -option caps:backspace

lgarron · 2014-10-27 22:53:39 9
Print one . instead of each line

If you're running a command with a lot of output, this serves as a simple progress indicator. This avoids the need to use `/dev/null` for silencing. It works for any command that outputs lines, updates live (`fflush` avoids buffering), and is simple to understand. Show Sample Output
This is sample output - yours may be different.
```
$ ls ~ | ...
..............
```
7

alias ...="awk '{fflush(); printf \".\"}' && echo \"\""

lgarron · 2014-02-22 22:20:22 18
Find last reboot time

Specific to OSX. Show Sample Output
This is sample output - yours may be different.
```
kern.boottime = Wed Jan 22 00:41:33 2014
```
1

sysctl -a | grep boottime | head -n 1

lgarron · 2014-01-24 13:03:48 9

This *does not change the video encoding*, so it's fast (almost purely I/O-bound) and results in a file of nearly the same size. However, OSX (and possibly other programs) will more easily play/seek the file when wrapped as MOV. For example, you can QuickLook the resulting file. This basically does the same as the commercial ClipWrap program, except using the free program ffmpeg. Show Sample Output

ffmpeg -i "input.mts" -vcodec copy -acodec pcm_s16le "output.mov"

lgarron · 2014-01-24 13:00:07 7

Copy modification timestamp from one file to another.
This is sample output - yours may be different.
1

touch -r "source_file" "destination_file"

lgarron · 2014-01-24 12:50:49 7
Copy to clipboard in addition to stdout (OSX).

Very convenient to for sending data to the clipboard for processing. However, note that tee will affect the buffering of the output (stdout won't be update very live). Show Sample Output
This is sample output - yours may be different.
```
$ echo "Hi" | t
Hi
$ pbpaste
Hi
```
0

alias t="tee >(pbcopy)"

lgarron · 2014-01-24 12:41:07 10

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Show all mergeinfo for a svn subtree

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Create more threads with less stack space

default stack size is 10M. This makes your multithread app filling rapidly your memory. on my PC I was able to create only 300thread with default stack size. Lower the default stack size to the one effectively used by your threads, let you create more. ex. putting 64k I was able to create more than 10.000threads. Obviously ...your thread shouldn't need more than 64k ram!!!

Compare two CSV files, discarding any repeated lines

The value for the sort command's -k argument is the column in the CSV file to sort on. In this example, it sorts on the second column. You must use some form of the sort command in order for uniq to work properly.

Convert numbers to SI notation

converts any number on the 'stdin' to SI notation. My version limits to 3 digits of precious (working with 10% resistors).

generate iso

Print line immediately before a matching regex.

Use this if you don't have access to GNU grep's -B option.

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Create a 5 MB blank file

Useful for testing purposes

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