Commands using sed (1,319)

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Convert JSON to YAML
You need to install the Catmandu Perl module via `cpanm Catmandu`

FizzBuzz in one line of Bash
The (in)famous "FizzBuzz" programming challenge, answered in a single line of Bash code. The "|column" part at the end merely formats the output a bit, so if "column" is not installed on your machine you can simply omit that part. Without "|column", the solution only uses 75 characters. The version below is expanded to multiple lines, with comments added. for i in {1..100} # Use i to loop from "1" to "100", inclusive. do ((i % 3)) && # If i is not divisible by 3... x= || # ...blank out x (yes, "x= " does that). Otherwise,... x=Fizz # ...set x to the string "Fizz". ((i % 5)) || # If i is not divisible by 5, skip (there's no "&&")... x+=Buzz # ...Otherwise, append (not set) the string "Buzz" to x. echo ${x:-$i} # Print x unless it is blanked out. Otherwise, print i. done | column # Wrap output into columns (not part of the test).

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Rename files in batch

Run a program transparently, but print a stack trace if it fails
For automated unit tests I wanted my program to run normally, but if it crashed, to add a stack trace to the output log. I came up with this command so I wouldn't have to mess around with core files. The one downside is that it does smoosh your program's stderr and stdout together.

Send command to all terminals in a screen session

show how many regex you use in your vim today
i want to count how many regex code i have used in vim in a long time so i make a directory in svn host and post record to this directory of course i dont want to post manually so i worte a script to do that and this is the core thing to do

Use top to monitor only all processes with the same name fragment 'foo'
$ pgrep foo may return several pids for process foobar footy01 etc. like this: 11427 12576 12577 sed puts "-p " in front and we pass a list to top: $ top -p 11427 -p 12576 -p 12577

generate iso

Execute matlab sentences from command line
Execute matlab sentences in shell script: for var in `seq 0 0.2 1` ; do echo "my_function($var);" | matlab -nodisplay done


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