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Another Matrix Style Implementation

check open ports without netstat or lsof

Convert seconds to [DD:][HH:]MM:SS
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" }

Convert seconds to [DD:][HH:]MM:SS
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" }

Rename all files which contain the sub-string 'foo', replacing it with 'bar'
Would this command line achieve the desired function? My CLI knowledge is not great so this could certainly be wrong. It is merely a suggestion for more experienced uses to critique. Best wishes roly :-)

Alert visually until any key is pressed
I learned a few things reading this command. But I did run into a few issues: 1. On systems that don't use GNU echo (e.g. macOS 10.14.5 Mojave), the e option may not be supported. In this case ANSI escape codes will echoed as text and the terminal will not flash, like this: \e[?5h\e[38;5;1m A L E R T Thu Jun 20 16:31:29 PDT 2019 2. Since the read command strips\ignores leading backslashes, if a user types the backslash character once in the loop, it will not break. Typing backslash twice in a loop will break as expected. 3. The foreground color is set to red (\e[38;5;1m) on every loop. This could be set once before we call while, and then reset once when the loop breaks. 4. Instead of resetting the foreground color when it breaks, the video mode is set back to normal (\e[?5l). This has the effect of leaving the terminal text red until it is manually reset. The alternative I'm proposing here addresses these issues. I tested it on macOS and Arch Linux.

Simulate typing
this also generates errors (change 4 to higher number for more mistakes)

Updating to Fedora 11

quick integer CPU benchmark
This is a quick and dirty way to generate a (non-floating-point) CPU-bound task to benchmark. Adjust "20" to higher or lower values, as needed. As a benchmark this is probably a little less bogus than bogomips, and it will run anywhere 'bc' does.

Update zone file Serial numbers
Will edit *.db files in the same directory with todays date. Useful for doing a mass update to domains on a nameserver, adding spf records, etc. Looks for a string starting with 200 or 201 followed by 7 numbers, and replaces with todays date. This won't overwrite Ip's but i would still do some double checking after running this. Make sure your server's date is correct, otherwise insert your own serial number. $rndc reload should usually follow this command.


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