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Occasionally, to force zone updating, cache flush is necessary. This command is better than restart the mydns daemon.
rename file name with fixed length nomeric format pattern
Recent hardware may or may not enumerate *both of* these values
This is probably overkill, but I have some issues when the directories have spaces in their names.
The
$ find . -type d -print0 | while read -d $'\0' dir; do xxx; done
loops over all the subdirectories in this place, ignoring the white spaces (to some extend).
$ cd "$dir"; echo " process $dir"; cd -;
goes to the directory and back. It also prints some info to check the progress.
$ find . -maxdepth 1 -name "*.ogg.mp3" -exec rename 's/.ogg.mp3/.mp3/' {} \;
renames the file within the current directory.
The whole should work with directories and file names that include white spaces.
This command will give you a list of available keyboard shortcuts according to stty.
This captures traffic on a remote machine with tshark, sends the raw pcap data over the ssh link, and displays it in wireshark. Hitting ctrl+C will stop the capture and unfortunately close your wireshark window. This can be worked-around by passing -c # to tshark to only capture a certain # of packets, or redirecting the data through a named pipe rather than piping directly from ssh to wireshark. I recommend filtering as much as you can in the tshark command to conserve bandwidth. tshark can be replaced with tcpdump thusly:
$ ssh root@example.com tcpdump -w - 'port !22' | wireshark -k -i -
Rather than complicated and fragile paths relative to a script like "../../other", this command will retrieve the full path of the file's repository head. Safe with spaces in directory names. Works within a symlinked directory. Broken down:
$cd "$(dirname "${BASH_SOURCE[0]}")"
temporarily changes directories within this expansion. Double quoted "$(dirname" and ")" with unquoted ${BASH_SOURCE[0]} allows spaces in the path.
$git rev-parse --show-toplevel
gets the full path of the repository head of the current working directory, which was temporarily changed by the "cd".
Thanks to flatcap for optimizing this command.
This command takes advantage of the ext4 filesystem's resistance to fragmentation.
By using this command, files that were previously fragmented will be copied / deleted / pasted essentially giving the filesystem another chance at saving the file contiguously. ( unlike FAT / NTFS, the *nix filesystem always try to save a file without fragmenting it )
My command only effects the home directory and only those files with your R/W (read / write ) permissions.
There are two issues with this command:
1. it really won't help, it works, but linux doesn't suffer much (if any ) fragmentation and even fragmented files have fast I/O
2. it doesn't discriminate between fragmented and non-fragmented files, so a large ~/ directory with no fragments will take almost as long as an equally sized fragmented ~/ directory
The benefits i managed to work into the command:
1. it only defragments files under 16mb, because a large file with fragments isn't as noticeable as a small file that's fragmented, and copy/ delete/ paste of large files would take too long
2. it gives a nice countdown in the terminal so you know how far how much progress is being made and just like other defragmenters you can stop at any time ( use ctrl+c )
3. fast! i can defrag my ~/ directory in 11 seconds thanks to the ramdrive powering the command's temporary storage
bottom line:
1. its only an experiment, safe ( i've used it several times for testing ), but probably not very effective ( unless you somehow have a fragmentation problem on linux ). might be a placebo for recent windows converts looking for a defrag utility on linux and won't accept no for an answer
2. it's my first commandlinefu command
This will merge all of the changes from {rev_num} to head on the branch to the current working directory