Commands tagged exclude binary (2)

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Recursive cat - concatenate files (filtered by extension) across multiple subdirectories into one file
Useful if you have to put together multiple files into one and they are scattered across subdirectories. For example: You need to combine all .sql files into one .sql file that would be sent to DBAs as a batch script. You do get a warning if you create a file by the same extension as the ones your searching for. find . -type f -name *.sql -exec cat {} > BatchFile.txt \;

Displays process tree of all running processes
G - uses VT100 line drawing a - shows command line arguments of process p - prints PID of process For other options, man pstree :)

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"

Quickly (soft-)reboot skipping hardware checks
If you are doing some tests which require reboots (e. g. startup skripts, kernel module parameters, ...), this is very time intensive, if you have got a hardware with a long pre-boot phase due to hardware checks. At this time, kexec can help, which only restarts the kernel with all related stuff. First the kernel to be started is loaded, then kexec -e jumps up to start it. Is as hard as a reboot -f, but several times faster (e. g. 1 Minute instead of 12 on some servers here).

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

Display Spinner while waiting for some process to finish
alternatively, run the spinner for 5 seconds: timeout 5 bash -c 'spinner=( Ooooo oOooo ooOoo oooOo ooooO oooOo ooOoo oOooo); while true; do for i in ${spinner[@]}; do for j in seq 0 ${#i}; do echo -en "\b\b"; done; echo -ne "${i}"; sleep 0.2; done; done'

Using bash inline
There are two ways to use "here documents" with bash to fill stdin: The following example shows use with the "bc" command. a) Using a delimiter at the end of data: $ less-than less-than eeooff bc > k=1024 > m=k*k > g=k*m > g > eeooff 1073741824 b) using the "inline" verion with three less-than symbols: $ less-than less-than less-than "k=1024; m=k*k; g=k*m; g" bc 1073741824 One nice advantage of using the triple less-than version is that the command can easily be recalled from command line history and re-executed. PS: in this "description", I had to use the name "less-than" to represent the less-than symbol because the commandlinefu input text box seems to eat up the real less-than symbols. Odd.

Sort a character string
Sorts a character string, using common shell commands.

find all active IP addresses in a network

follow the content of all files in a directory
The `-q' arg forces tail to not output the name of the current file

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