Commands by rpavlick (15)

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prevents replace an existing file by mistake
Use set +o noclobber and you will be able to replace files again

Remove all unused kernels with apt-get
This should do the same thing and is about 70 chars shorter.

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" }

The fastest remote directory rsync over ssh archival I can muster (40MB/s over 1gb NICs)
This creates an archive that does the following: rsync:: (Everyone seems to like -z, but it is much slower for me) -a: archive mode - rescursive, preserves owner, preserves permissions, preserves modification times, preserves group, copies symlinks as symlinks, preserves device files. -H: preserves hard-links -A: preserves ACLs -X: preserves extended attributes -x: don't cross file-system boundaries -v: increase verbosity --numeric-ds: don't map uid/gid values by user/group name --delete: delete extraneous files from dest dirs (differential clean-up during sync) --progress: show progress during transfer ssh:: -T: turn off pseudo-tty to decrease cpu load on destination. -c arcfour: use the weakest but fastest SSH encryption. Must specify "Ciphers arcfour" in sshd_config on destination. -o Compression=no: Turn off SSH compression. -x: turn off X forwarding if it is on by default. Flip: rsync -aHAXxv --numeric-ids --delete --progress -e "ssh -T -c arcfour -o Compression=no -x" [source_dir] [dest_host:/dest_dir]

Python extract json

Scan for new SCSI devices
Issues a scan command on the given scsi host adapter (ex. a fibre channel adapter, in the example above on host0). Output can be watched in the messages log or in "dmesg"

Print all commands of a user on commandlinefu.com
This utilizes the Requests and BeautifulSoup libraries in Python to retrieve a user page on commandlinefu, parse it (error-tolerant) and extract all the lines of the following format: gzip * To print them, a list comprehension is used to iterate over the values, and join() is called on a newline character.

"Pretty print" $PATH, separate path per line
from: http://www.unix.com/shell-programming-and-scripting/28047-split-print-path.html

Shows the torrent file name along with the trackers url
Replace * with any filename matching glob or an individual filename

get all Amazon cloud (amazonws etc) ipv6 subnets


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