Commands tagged dns (38)

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Display condensed log in a tree-like format.
Display condensed log in a tree-like format.

Wait for file to stop changing
Here's a way to wait for a file (a download, a logfile, etc) to stop changing, then do something. As written it will just return to the prompt, but you could add a "; echo DONE" or whatever at the end. This just compares the full output of "ls" every 10 seconds, and keeps going as long as that output has changed since the last interval. If the file is being appended to, the size will change, and if it's being modified without growing, the timestamp from the "--full-time" option will have changed. The output of just "ls -l" isn't sufficient since by default it doesn't show seconds, just minutes. Waiting for a file to stop changing is not a very elegant or reliable way to measure that some process is finished - if you know the process ID there are much better ways. This method will also give a false positive if the changes to the target file are delayed longer than the sleep interval for any reason (network timeouts, etc). But sometimes the process that is writing the file doesn't exit, rather it continues on doing something else, so this approach can be useful if you understand its limitations.

Speaking alarm clock
This ran on a ubuntu box using espeak for speaking text with the bash shell. On a mac you should use 'say'. Also you can change your alarm interval and your snooze interval which are currently 8 hours and 1 minute. I would run this via cron yet it's easier to disable if you run it as a command like this :P

Create a new file

Take a screenshot of the focused window with a 4 second countdown
Take a screenshot of the focused window with a 4 second countdown # shorten by adding to your .bashrc: alias sss='scrot -ucd4 && eog $(ls -tr | tail -n1)' $ echo -e "\nalias sss='scrot -ucd4 && eog $(ls -tr | tail -n1)'" >> ~/.bashrc -d 4 second delay -c display countdown -u focused window man scrot for more flags

Generate hash( of some types) from string
No need to install yet another program when openssl is already installed. :-)

grep -v with multiple patterns.
If you wanted to do all in one command, you could go w/ sed instead

list with full path

Instantly load bash history of one shell into another running shell
By default bash history of a shell is appended (appended on Ubuntu by default: Look for 'shopt -s histappend' in ~/.bashrc) to history file only after that shell exits. Although after having written to the history file, other running shells do *not* inherit that history - only newly launched shells do. This pair of commands alleviate that.

Print a horizontal line


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