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First argument: string to put a box around.
Second argument: character to use for box (default is '=')
Same as command #4948, but shorter, and without the utility function.
Instead of deleting an existing symlink and then re-creating it pointing at the new location, it is possible to perform the same action with this one command.
Interesting discussion on whether this is possible to do atomically here: http://answers.google.com/answers/threadview?id=526119
Shows a tree view of parent to child processes in the output of ps (linux). Similar output can be achieved with pstree (also linux) or ptree (Solaris).
Run netstat as root (via sudo) to get the ID of the process listening on the desired socket.
Use awk to 1) match the entry that is the listening socket, 2) matching the exact port (bounded by leading colon and end of column), 3) remove the trailing slash and process name from the last column, and finally 4) use the system(…) command to call kill to terminate the process.
Two direct commands, netstat & awk, and one forked call to kill.
This does kill the specific port instead of any port that starts with 50. I consider this to be safer.
Converts any number of seconds into days, hours, minutes and seconds.
sec2dhms() {
declare -i SS="$1"
D=$(( SS / 86400 ))
H=$(( SS % 86400 / 3600 ))
M=$(( SS % 3600 / 60 ))
S=$(( SS % 60 ))
[ "$D" -gt 0 ] && echo -n "${D}:"
[ "$H" -gt 0 ] && printf "%02g:" "$H"
printf "%02g:%02g\n" "$M" "$S"
}
Directories listed in human-readable format
This will encrypt your single file and create a filename.gpg file.
Option: * -c : Encrypt with symmetric cipher
To decrypt
dhinesh@ubuntu:~$ gpg -c sample.rb.gpg
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
For instance:
$ find . -type f -name '*.wav' -print0 |xargs -0 -P 3 -n 1 flac -V8
will encode all .wav files into FLAC in parallel.
Explanation of xargs flags:
-P [max-procs]: Max number of invocations to run at once. Set to 0 to run all at once [potentially dangerous re: excessive RAM usage].
-n [max-args]: Max number of arguments from the list to send to each invocation.
-0: Stdin is a null-terminated list.
I use xargs to build parallel-processing frameworks into my scripts like the one here: http://pastebin.com/1GvcifYa
