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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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Use this command to watch apache access logs in real time to see what pages are getting hit.
The files are automatically uncompressed when they reach the destination machine. This is a fast way to backup your server to your local computer while it's running (shutting down services is recommended).
A file named "exclude.txt" is needed at /tmp/ containing the following :
solution that works for me
xmllint2 comes with GNU libxml2 library.
List all files in a directory in reverse order by modified timestamp. When piped through tail the user will see the most recent file name.
Consider the following simple situation [ reading something using while and read ]
[See script 1 in sample output]
The variable var is assigned with "nullll" at first. Inside the while loop [piped while] it is assigned with "whillleeee". [Onlly 2 assignments stmts]. Outside the loop the last assigned value for "var" [and no variable] inside the while can't be accessed [Due to pipe, var is executed in a sub shell].
In these type of situation variables can be accessed by modifying as follows.
[See script 2 in sample output]
Vary helpful when reading a set of items, say file names, stored on a file [or variable] to an array an use it later.
Is there any other way 2 access variables inside and outside the loop ??
This is shorter and actually much faster than >/dev/null (see sample output for timings)
Plus, it looks like a disappointed face emoticon.
Better solution in case of many clients, imo.
`tar xfzO` extracts to STDOUT which got redirected directly to mysql. Really helpful, when your hard drive can't fit two copies of non-compressed database :)
run 'nc yourip 5000', 'nc yourip 5001' or 'nc yourip 5002' elsewhere will produce an exact same mirror of your shell. This is handy when you want to show someone else some amazing stuff in your shell without giving them control over it.
Tee can be used to split a pipe into multiple streams for one or more process to work it. You can add more " >()" for even more fun.
PDF files are simultaneously wonderful and heinous. They are wonderful in being ubiquitous and mostly being cross platform. They are heinous in being very difficult to work with from the command line, search, grep, use only the text inside the PDF, or use outside of proprietary products.
xpdf is a wonderful set of PDF tools. It is on many linux distros and can be installed on OS X. While primarily an open PDF viewer for X, xpdf has the tool "pdftotext" that can extract formated or unformatted text from inside a PDF that has text. This text stream can then be further processed by grep or other tool. The '-' after the file name directs output to stdout rather than to a text file the same name as the PDF.
Make sure you use version 3.02 of pdftotext or later; earlier versions clipped lines.
The lines extracted from a PDF without the "-layout" option are very long. More paragraphs. Use just to test that a pattern exists in the file. With "-layout" the output resembles the lines, but it is not perfect.
xpdf is available open source at http://www.foolabs.com/xpdf/
If you have some drive imaging to do, you can boot into any liveCD and use a commodity machine. The drives will be written in parallel.
To improve efficiency, specify a larger block size in dd:
dd if=/dev/sda bs=64k | tee >(dd of=/dev/sdb bs=64k) | dd of=/dev/sdc bs=64k
To image more drives , insert them as additional arguments to tee:
dd if=/dev/sda | tee >(dd of=/dev/sdb) >(dd of=/dev/sdc) >(dd of=/dev/sdd) | dd of=/dev/sde
You can use [n]> combined with >(cmd) to attach the various output file descriptors to be the input of different commands.
sudo ipfw pipe 1 config bw 50KByte/s
Set the bandwidth (bw) limit to any number you want. For example you could have a 15kb pipe for X application and then a 100kb pipe for another application and attach things to those pipes. If a port isn’t attached to a pipe, it runs at full speed. Change the number (in this case 1) to a different number for a different pipe.
The next step is to attach your port.
sudo ipfw add 1 pipe 1 src-port 80
In this case anything on port 80 (http) will be set to a limit of 50Kbyte/s. If you want to attach a second port to this pipe, repeat the command but change the port number at the end.