Commands using echo (1,545)

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

count how many cat processes are running
'ps ax' provides the fill list of running processes. 'grep -c [c]at' will find all processes that match 'cat' without matching itself....

Safe Delete
remove file that has sensitive info safely. Overwrites it 33 times with zeros

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

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"

Remove a line from a file using sed (useful for updating known SSH server keys when they change)
For example, to remove line 5 from foo, type: vi +5d +wq foo

Replace duplicate files by hardlinks
This variation can handle file paths containing spaces.

Download Youtube video with wget!
Nothing special required, just wget, sed & tr!

True random passwords using your microphone noise as seed
Generate a truly random password using noise from your microphone to seed the RNG. This will spit out 12 password with 12 characters each, but you can save this into a bash script and replace 'pwgen -ys 12 12' with 'pwgen $@' so you can pass any paramters to pwgen as you would normally do.

convert a latex source file (.tex) into opendocument (.odt ) format
require the tex4ht package . You can open the file with openoffice , I use it much for correct my spelling and grammar .


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