Commands by flarn2006 (4)

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Delete recursively only empty folders on present dir

Create a file of a given size in linux
If you're trying to create a sparse file, you can use dd by 'skip'ing to the last block instance. ls -ls shows the actual size vs. the reported size

Best SSH options for X11 forwarding
grabbed from: http://blog.samat.org/2006/05/08/best-ssh-options-for-x11-forwarding

Find all the files more than 10MB, sort in descending order of size and record the output of filenames and size in a text file.
This command specifies the size in Kilobytes using 'k' in the -size +(N)k option. The plus sign says greater than. -exec [cmd] {} \; invokes ls -l command on each file and awk strips off the values of the 5th (size) and the 9th (filename) column from the ls -l output to display. Sort is done in reversed order (descending) numerically using sort -rn options. A cron job could be run to execute a script like this and alert the users if a dir has files exceeding certain size, and provide file details as well.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

VIM: when Ctrl-D and Ctrl-U only scroll one line, reset to default
Resets the scroll parameter to the default (half the rows in the current window). The scroll parameter can be inadvertently set to 1, e..g., if you type '1 Ctrl-D' or '1 Ctrl-U' in normal mode.

Create a directory and change into it at the same time
How often do you make a directory (or series of directories) and then change into it to do whatever? 99% of the time that is what I do. This BASH function 'md' will make the directory path then immediately change to the new directory. By using the 'mkdir -p' switch, the intermediate directories are created as well if they do not exist.

Fastest Sort. Sort Faster, Max Speed
sort is way slow by default. This tells sort to use a buffer equal to half of the available free memory. It also will use multiple process for the sort equal to the number of cpus on your machine (if greater than 1). For me, it is magnitudes faster. If you put this in your bash_profile or startup file, it will be set correctly when bash is started. $ sort -S1 --parallel=2 /dev/null && alias sortfast='sort -S$(($(sed '\''/MemF/!d;s/[^0-9]*//g'\'' /proc/meminfo)/2048)) $([ `nproc` -gt 1 ]&&echo -n --parallel=`nproc`)' Alternative $ echo|sort -S10M --parallel=2 &>/dev/null && alias sortfast="command sort -S$(($(sed '/MemT/!d;s/[^0-9]*//g' /proc/meminfo)/1024-200)) --parallel=$(($(command grep -c ^proc /proc/cpuinfo)*2))"

Search some text from all files inside a directory

Extract tarball from internet without local saving

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