Commands by pebkac (4)

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Find files and calculate size of result in shell
Use find's internal stat to get the file size then let the shell add up the numbers.

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

send DD a signal to print its progress
Sends the "USR1" signal every 1 second (-n 1) to a process called exactly "dd". The signal in some systems can be INFO or SIGINFO ... look at the signals list in: man kill

full path listing in /directory/path/* of javascript files.
file listing in /directory/path/* of specific files such as javascript(js) .

Get the current svn branch/tag (Good for PS1/PROMPT_COMMAND cases)
uses just one sed

easily strace all your apache processes
Will open strace on all apache process, on systems using sbin/apache (debian) or sbin/httpd (redhat), and will follow threads newly created.

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

Swap the two last arguments of the current command line
Say you just typed a long command like this: $ rsync -navupogz --delete /long/path/to/dir_a /very/long/path/to/dir_b but you really want to sync dir_b to dir_a. Instead of rewriting all the command line, just type followed by , and your command line will read $ rsync -navupogz --delete /very/long/path/to/dir_b /long/path/to/dir_a

Short one line while loop that outputs parameterized content from one file to another
The above is an example of grabbing only the first column. You can define the start and end points specifically by chacater position using the following command: $ while read l; do echo ${l:10:40}; done < three-column-list.txt > column-c10-c40.txt Of course, it doesn't have to be a column, or extraction, it can be replacement $ while read l; do echo ${l/foo/bar}; done < list-with-foo.txt > list-with-bar.txt Read more about parameter expansion here: http://wiki.bash-hackers.org/syntax/pe Think of this as an alternative to awk or sed for file operations

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"


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