Ruby - catch SIGINT to allow finishing of file writing - ruby

Question

I know how to catch a SIGINT, but I only know how to put the block somewhere random in my code. I need to be able to catch SIGINT because if file writing is in progress (my database writes to a file frequently), it corrupts the file. What's the ideal way to handle this?
Edit
In one instance, I handled this by executing my writing function if I detect a SIGINT, but I'm realizing this won't help if I'm literally in the middle of writing to a file using Marshal.
Is there no way in Ruby to catch a SIGINT and tell it to ignore it until it, for example, finishes writing?
Edit 2
Nevermind, just figured out a possible answer... see below.

Answer 1

I ended up using a rescue block, which rescues Interrupt. In the block, I turn a boolean to true. The boolean is checked at the beginning of each of my thread pool tasks and if its true, skips the entire function.
Edit
In regards to my edit in my original post: Would the best way to handle interrupts in file writing be to use a boolean again? For example, create a boolean called interrupt and at the end of writing to the file, check to see if boolean is true and if so, abort the program? I couldn't use a rescue to catch the interrupt then, but I could use trap, no?

Answer 2

That's what I would do :
Signal.trap("INT"){
if $lock
puts "Not yet done. Please don't interrupt"
else
puts "Goodbye!"
exit
end
}
def something_long_that_shouldnt_be_interrupted
$lock = true
10.times do |i|
puts "Writing #{i+1}/10. Don't interrupt"
sleep 1
end
$lock = false
end
def some_other_process_that_can_be_interrupted
10.times do |i|
puts "Unimportant stuff #{i+1}/10."
sleep 1
end
end
something_long_that_shouldnt_be_interrupted
some_other_process_that_can_be_interrupted
# Writing 1/10. Don't interrupt
# Writing 2/10. Don't interrupt
# ^CNot yet done. Please don't interrupt
# Writing 3/10. Don't interrupt
# Writing 4/10. Don't interrupt
# ^CNot yet done. Please don't interrupt
# Writing 5/10. Don't interrupt
# ^CNot yet done. Please don't interrupt
# ^CNot yet done. Please don't interrupt
# Writing 6/10. Don't interrupt
# ^CNot yet done. Please don't interrupt
# Writing 7/10. Don't interrupt
# Writing 8/10. Don't interrupt
# ^CNot yet done. Please don't interrupt
# Writing 9/10. Don't interrupt
# Writing 10/10. Don't interrupt
# Unimportant stuff 1/10.
# Unimportant stuff 2/10.
# Unimportant stuff 3/10.
# Unimportant stuff 4/10.
# ^CGoodbye!
If you use it more than once, you could define :
def do_not_disturb(&block)
$lock = true
block.yield
$lock = false
end
do_not_disturb do
# code that shouldn't be interrupted
end