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find the 10 latest (modified) files
order the files by modification (thanks stanishjohnd) time, one file per output line and filter first 10

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

git diff of files that have been staged ie 'git add'ed

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"

livehttpheaders (firefox addon) replacement
Default output-file is "liveh.txt". This uses only BRE, in case you're using an older version of sed(1) that doesn't have support for ERE added. With a modern sed(1), to reduce false positive matches, you might do something like: liveh(){ tcpdump -lnnAs512 -i ${1-} tcp |sed 's/.*GET /GET /;s/.*Host: /Host: /;s/.*POST /POST /;/GET |Host: |POST /!d;/[\"'"'"]/d;/\.\./d;w '"${2-liveh.txt}"'' >/dev/null ;} Anyway, it's easy to clean up the output file with sed(1) later.

Email yourself a short note
I created this so I could send myself an email alert when a long-running job was finished, e.g., $ my_long_job.exe ; quickemail my_long_job.exe has finished

Show the command line of a process that use a specific port (ubuntu)

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Use socat to emulate an SMTP mail SERVER
Lots of scripts show you how to use socat to send an email to an SMTP server; this command actually emulates an SMTP server! It assumes the client is only sending to one recipient, and it's not at all smart, but it'll capture the email into a log file and the client will stop retrying. I used this to diagnose what emails were being sent by cron and subsequently discarded, but you can use it for all sorts of things.

Break lines after, for example 78 characters, but don't break within a word/string
Per default, linux/unix shells are configured with a width of 80 characters. If you like to edit a phrase or string on a line with more than 80 characters it might take long to go there (for example a line with 1000 characters and you like to edit the 98th word which is character 598-603). Maybe you might wish to use 78 characters, because if you forward the text via mail and the text will be quoted (2 extra characters at the beginning to the line "> "), you use 80 characters, otherwise 82, which are lame.


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