Essentially, I have a standard format for file naming conventions. It breaks down to this:
target_dateUTC_timeUTC_tool
So, for instance, if I run tcpdump on a target of 'foo', then the file would be foo_dateUTC_timeUTC_tcpdump. Simple enough, but a pain for everyone to constantly (and consistently) enter... so I've tried to create a bash script which sets system variables like so:
FILENAME=$TARGET\_$UTCTIME\_$TOOL
Then, I can just call the variable at runtime, like so:
tcpdump -w $FILENAME.lpc
All of this works like a champ. I've got a menu-driven .sh which gives the user the options of viewing the current variables as well as setting them... file generation is a breeze. Unfortunately, by setting the date/time variable, it is locked to the value at the time of creation (naturally). I set the variable like so:
UTCTIME=$(/bin/date --utc +"%Y%m%d_%H%M%Z")
What I really need is either a way to create a variable which updates at runtime, or (more likely) another way to skin this cat.
While scouring for solutions, I came across a similar issues... like this.
But, to be honest, I'm stumped on how to marry the two approaches and create a simple, distributable solution.
.sh file is posted via pastebin, here.
Use a function:
generate_filename() { echo "${1}_$(/bin/date --utc +"%Y%m%d_%H%M%Z")_$2"; }
And use it like this:
tcpdump -w "$(generate_filename foo tcpdump).lpc"
It's hard to get the function to automatically determine the command name. You can use bash history to get it and save a couple of characters typing:
tcpdump -w "$(generate_filename foo !#:0).lpc"