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Submit command & rewrite orginal command
Similar to entering a command, but will not erase the command from the command line. Basically a shortcut from entering command, then pushing the up arrow key.

list files recursively by size

Check a directory of PNG files for errors
Useful for checking if a large number of PNG files was downloaded successfully by verifying the built-in CRC checksum. For incomplete files, the command will print: "00002309.png EOF while reading IDAT data ERROR: 00002309.png" The process is very fast; checking 21,000 files of 5MB in size took only five minutes on a 2011 Intel mobile dual-core.

Split a large file, without wasting disk space
It's common to want to split up large files and the usual method is to use split(1). If you have a 10GiB file, you'll need 10GiB of free space. Then the OS has to read 10GiB and write 10GiB (usually on the same filesystem). This takes AGES. . The command uses a set of loop block devices to create fake chunks, but without making any changes to the file. This means the file splitting is nearly instantaneous. The example creates a 1GiB file, then splits it into 16 x 64MiB chunks (/dev/loop0 .. loop15). . Note: This isn't a drop-in replacement for using split. The results are block devices. tar and zip won't do what you expect when given block devices. . These commands will work: $ hexdump /dev/loop4 . $ gzip -9 < /dev/loop6 > part6.gz . $ cat /dev/loop10 > /media/usb/part10.bin

Copy all files, including hidden files, recursively without traversing backward
You could do the following, however, brace expansion with {} is not defined in POSIX, and therefore not guaranteed to work in all shells. But, if it does, it's more convenient (although it's certainly not less typing): $ cp -r {*,.??*} /dest Sometimes there are times when I need to cp(1), mv(1) or rm(1) files recursively, but don't want to traverse the previous directory by following ../../../../ etc out of the current directory. This command prevents that. The secret sauce is ".??*". The file globbing ensures that it must start with a dot, and be followed by at least two characters. So, three characters must exist in the filename, which eliminates "." and "..".

Comment current line
This should work with different locales. Another post reports

DVD ripping with ffmpeg
Alternative, imho better, using the concat protocol

Display the tree of all instance of a particular process

grep for minus (-) sign
Use flag "--" to stop switch parsing

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials


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