Commands using head (314)

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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

Share your terminal session (remotely or whatever)
Force the user you want to watch doing things into doing his things in a screen session. Then simply attach yourself to that session with the command shown above. Works only if you are on the same machine, of course

Randomize lines in a file
This appends a random number as a first filed of all lines in SOMEFILE then sorts by the first column and finally cuts of the random numbers.

send a message to a windows machine in a popup
It will only work if the service NETSEND in the Windows machine is enabled.

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously

list current processes writing to hard drive

Carriage return for reprinting on the same line
The above code is just an example of printing on the same line, hit Ctrl + C to stop When using echo -ne "something\r", echo will: - print "something" - dont print a new line (-n) - interpret \r as carriage return, going back to the start of the line (-e) Remember to print some white spaces after the output if your command will print lines of different sizes, mainly if one line will be smaller than the previous Edit from reading comments: You can achieve the same effect using printf (more standardized than echo): while true; do printf "%-80s\r" "$(date)"; sleep 1; done

Download file with multiple simultaneous connections
jrk's aria2 example is incorrect. -s specifies the global connection limit; the per-host connection limit is specified with -x.

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)


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