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Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):
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Article mentions what each part of the command is responsible for.
Search in all html files and remove the lines that 'String' is found.
In general, this is actually not better than the "scrot -d4" command I'm listing it as an alternative to, so please don't vote it down for that. I'm adding this command because xwd (X window dumper) comes with X11, so it is already installed on your machine, whereas scrot probably is not. I've found xwd handy on boxen that I don't want to (or am not allowed to) install packages on.
NOTE: The dd junk for renaming the file is completely optional. I just did that for fun and because it's interesting that xwd embeds the window title in its metadata. I probably should have just parsed the output from file(1) instead of cutting it out with dd(1), but this was more fun and less error prone.
NOTE2: Many programs don't know what to do with an xwd format image file. You can convert it to something normal using NetPBM's xwdtopnm(1) or ImageMagick's convert(1). For example, this would work: "xwd | convert fd:0 foo.jpg". Of course, if you have ImageMagick already installed, you'd probably use import(1) instead of xwd.
NOTE3: Xwd files can be viewed using the X Window UnDumper: "xwud <foo.xwd". ImageMagick and The GIMP can also read .xwd files. Strangely, eog(1) cannot.
NOTE4: The sleep is not strictly necessary, I put it in there so that one has time to raise the window above any others before clicking on it.
if you use disk-based swap then it can defeat the purpose of this function.
Renames files in a directory to incremental numbers, following alphabetic order. The command does not maintain extensions.
rename is a great command, but can't get it to work on mac.
Prepends all directory items with "prependtext"
all files in the directory get moved, in doing so the new name of the file is the original name with out spaces (using translate command)
This heavy one liner gets all the files in the "/music/dir/" directory and filters for non 44.1 mp3 files. After doing this it passes the names to sox in-order to re-sample those files. The original files are left just in case.
Thanks th John_W for suggesting the fix allowing ~/ to be used when saving a directory.
Type in a url, it will show a preview of what the file will look like when saved, then asks if you want to save the preview and where you want to save it. Great for grabbing the latest commandlinefu commands without a full web browser or even a GUI. Requires: w3m
I wrote this script to speed up Nginx configs. This (long) one liner can be run via BASH. You will see that we set a variable in bash called 'foo' and the streamline editor (sed) finds 'bar' in 'foo.conf' next it writes that output to a temp file (foo.temp) and removes the first 5 lines (that aren't needed in this case) & lastly it moves (overwrites) foo.temp to foo.conf
We normally get tasks in which one has to sort a data file according to some column. For a single file say foo, we would use
sort -k 3 foo >tmp && tmp foo
The for loop is useful when we have to do it on a number of files.
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
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
Checks if a web page has changed. Put it into cron to check periodically.
Change http://www.page.de/test.html and firstname.lastname@example.org for your needs.
In a folder with many files and folders, you want to move all files where the date is >= the file olderFilesNameToMove and
Simple bash/ksh/sh command to rename all files from lower to upper case. If you want to do other stuff you can change the tr command to a sed or awk... and/or change mv to cp....
This renames a pattern matched bunch of files by their last modified time.
rename by timestamp
rename by time created
rename by time modified