Check These Out
If you vim a compressed file it will list all archive content, then you can pickup any of them for editing and saving. There you have the modified archive without any extra step. It supports many file types such as tar.gz, tgz, zip, etc.
Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.
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
Shows a simple clock in the console
-t param removes the watch header
Ctrl-c to exit
This takes a picture (with the web cam) every 5 minutes, and send the picture to your e-mail.
Some systems support
mail -a "References: "
so that all video surveillance emails are grouped in a single email thread.
To keep your inbox clean, it is still possible to filter and move to trash video surveillance emails (and restore these emails only if you really get robbed!)
For instance with Gmail, emails sent to me+trash@gmail.com can be filtered with "Matches: DeliveredTo:me+trash@gmail.com"
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"
}
Since Bash doesn't support two-dimensional arrays, you can limit your columns length by some big enough constant value ( in this example 100 ) and then index the array with i and j, or maybe write your own get() and set() methods to index the array properly like I implemented for example ( see Sample output ).
For example for i=0 and j=0...99 you'll pick up one of 100 elements in the range [0,99] in the one-dimensional array.
For i=1 and j=0...99 you'll pick up one of 100 elements in the range [100,199].
And so on.
Be careful when using this, and remember that in fact you are always using one-dimensional array.