Commands by IsraelTorres (9)

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Download a new release of a program that you already have very quickly
Zsync is an implementation of rsync over HTTP that allows updating of files from a remote Web server without requiring a full download. For example, if you already have a Debian alpha, beta or RC copy downloaded, zsync can just download the updated bits of the new release of the file from the server. This requires the distributor of the file to have created a zsync build control file (using zsyncmake).

Beep siren
Infinitely plays beeps with sinusoidally changing sound frequency. Ideal for alarm on an event.

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" }

Debug how files are being accessed by a process
Instead of looking through `lsof` results, use inotifywait!

print a file on a single line
Example: you have a package.txt you want to install on a system. Instead of this: cat package.txt package1 package2 package3 You want it to cat out on one line so you can print "yum install package1 package2 package3"

ROT13 using the tr command

show installed but unused linux headers, image, or modules
will show: installed linux headers, image, or modules: /^ii/!d avoiding current kernel: /'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d only application names: s/^[^ ]* [^ ]* \([^ ]*\).*/\1/ avoiding stuff without a version number: /[0-9]/!d

Slightly better compressed archives
Avoids creating useless directory entries in archive, and sorts files by (roughly) extension, which is likely to group similar files together for better compression. 1%-5% improvement.

find all active IP addresses in a network
Have to run as superuser... but easier and more informational if you are looking for actual devices. Need to install arp-scan.

Opens vi/vim at pattern in file
Open up vi or vim at the first instance of a pattern in [file]. Useful if you know where you want to be, like "PermitRootLogin" in sshd_config. Also, vi +10 [file] will open up a file at line 10. VERY useful when you get "error at line 10" type of output.


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