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-k, --keep-open will keep connection alive, and we could exclude using 'while true'
nc is such a powerful command, it could be used instead of any OS! :p
This example is taken from Cygwin running on Win7Ent-64. Device names will vary by platform.
Both commands resulted in identical files per the output of md5sum, and ran in the same time down to the second (2m45s), less than 100ms apart. I timed the commands with 'time', which added before 'dd' or 'readom' gives execution times after the command completes. See 'man time' for more info...it can be found on any Unix or Linux newer than 1973. Yeah, that means everywhere.
readom is supposed to guarantee good reads, and does support flags for bypassing bad blocks where dd will either fail or hang.
readom's verbosity gave more interesting output than dd.
On Cygwin, my attempt with 'readom' from the first answer actually ended up reading my hard drive. Both attempts got to 5GB before I killed them, seeing as that is past any CD or standard DVD.
'bs=1M' says "read 1MB into RAM from source, then write that 1MB to output. I also tested 10MB, which shaved the time down to 2m42s.
'if=/dev/scd0' selects Cygwin's representation of the first CD-ROM drive.
'of=./filename.iso' simply means "create filename.iso in the current directory."
'-v' says "be a little noisy (verbose)." The man page implies more verbosity with more 'v's, e.g. -vvv.
dev='D:' in Cygwin explicitly specifies the D-drive. I tried other entries, like '/dev/scd0' and '2,0', but both read from my hard drive instead of the CD-ROM. I imagine my LUN-foo (2,0) was off for my system, but on Cygwin 'D:' sort of "cut to the chase" and did the job.
f='./filename.iso' specifies the output file.
speed=2 simply sets the speed at which the CD is read. I also tried 4, which ran the exact same 2m45s.
retries=8 simply means try reading a block up to 8 times before giving up. This is useful for damaged media (scratches, glue lines, etc.), allowing you to automatically "get everything that can be copied" so you at least have most of the data.
use -xcvf to decompress
Useful for transferring large file over a network during operational hours
Useful for testing domain authentication through a Linux server
The "proportional set size" is probably the closest representation of how much active memory a process is using in the Linux virtual memory stack. This number should also closely represent the %mem found in ps(1), htop(1), and other utilities.
This uses mutt to send the file, and doesn't require uuencode etc
An entirely shell-based solution (should work on any bourne-style shell), more portable on relying on the rename command, the exact nature of which varies from distro to distro.
Info about Bluetooth devices.
Compares the md5 checksums of the contents of two directories, outputting the checksum and filename where any files differ. Shows only the file name, not the full path.
Compute the md5 checksums for the contents of two mirrored directories, then sort and diff the results. If everything matches, nothing is returned. Otherwise, any checksums which do not match, or which exist in one tree but not the other, are returned. As you might imagine, the output is useful only if no errors are found, because only the checksums, not filenames, are returned. I hope to address this, or that someone else will!
Optionally, pipe the output into http://sed.sourceforge.net/grabbag/scripts/html2iso.sed
Or: wget -qO - http://www.asciiartfarts.com/random.cgi | sed -n '//,//p' | sed -n '/
'/tmp/file 1.txt' '/tmp/file 2.jpg'
for Nautilus script
for Thunar action
If you linking the symlinks itself, but want to link to source files instead of symlinks, use
"`readlink -m "$i"`"
for i in '/tmp/file 1.txt' '/tmp/file 2.jpg'; do ln -s "`readlink -m "$i"`" "$i LINK"; done
RU: Найдет число файлов в папке по данной маске в цикле по дням месяца
How to figure out what a program is doing.
-tt detailed timestamps
-f also strace any child processes
-v be very verbose, even with common structures
-o write output to file
-s N capture up to N characters of strings, rather than abbreviating with ...
Batch resize all images to a width of 'X' pixels while maintaing the aspect ratio.
This makes uses of ImageMagick to make life easier.
The above is OK if you not worried about security, as per sshpass man pages:
" The -p option should be considered the least secure of all of sshpass's options. All system users can see the password in the command line with a simple "ps" command."
So, instead what I do is use the -e option:
" -e The password is taken from the environment variable "SSHPASS"."
You need to install "sshpass" for this to work.
apt-get install sshpass
I don't like doing a massive sort on all the directory names just to get a small set of them. the above shows a sorted list of all directories over 1GB. use head as well if you want.
du's "-x" flag limits this to one file system. That's mostly useful when you run it on "/" but don't want "/proc" and "/dev" and so forth. Remember though that it will also exclude "/home" or "/var" if those are separate partitions.
the "-a" option is often useful too, for listing large files as well as large directories. Might be slower.
list the top 15 folders by decreasing size in MB