Commands by dbr (4)

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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

download newest adminer and rename to it's version accordingly
If the version already downloaded. it will not download again

check open ports without netstat or lsof

Create md5sum of files under the current dir excluding some directories
Useful if you want get all the md5sum of files but you want exclude some directories. If your list of files is short you can make in one command as follow: $ find . -type d \( -name DIR1 -o -name DIR2 \) -prune -o -type f -exec md5sum {} \; Alternatively you can specify a different command to be executed on the resulting files.

Format partition with ext4 but without a journal
For slow flash memory (cheap thumb drive), ext4 is the fastest stable file system for all use cases with no relevant exception: http://www.linuxplanet.com/linuxplanet/tutorials/7208/1 Since we can usually dispense with the benefits of a journal for this type of storage, this is a way to achieve the least awful I/O-speed. Disabling the journal for an existing ext4 partition can be achieved using $ tune2fs -O ^has_journal /dev/sdXN Note that it is often recommended to format removable flash media with ext2, due to the lack of a journal. ext4 has many advantages over ext2 even without the journal, with much better speed as one of the consequences. So the only usecase for ext2 would be compatibility with very old software.

Dump HTTP header using wget
Let me suggest using wget for obtaining the HTTP header only as the last resort because it generates considerable textual overhead. The first ellipsis of the sample output stands for Spider mode enabled. Check if remote file exists. --2009-03-31 20:42:46-- http://www.example.com/ Resolving www.example.com... 208.77.188.166 Connecting to www.example.com|208.77.188.166|:80... connected. HTTP request sent, awaiting response... and the second one looks for Length: 438 [text/html] Remote file exists and could contain further links, but recursion is disabled -- not retrieving.

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

list block devices
Shows all block devices in a tree with descruptions of what they are.

Rename files in batch

Remind yourself to leave in 15 minutes
If you spend most of your time in front of the terminal, leave is a useful reminder. Leave can have absolute form: leave 1555 reminds you to leave at 3:55PM


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