Issue #8708 has been reported by bdimych (Dmitry Bolshakov).

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Bug #8708: It seems that a call to the "system" changes the handler of the INT signal
https://bugs.ruby-lang.org/issues/8708

Author: bdimych (Dmitry Bolshakov)
Status: Open
Priority: Normal
Assignee: 
Category: 
Target version: 
ruby -v: ruby 1.9.3p429 (2013-05-15) [i386-cygwin]
Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN


this is only on cygwin, on linux all ok
$ uname -a
CYGWIN_NT-5.1 bolshakovxp 1.7.21(0.267/5/3) 2013-07-15 12:17 i686 Cygwin


--- test script ---

#!/usr/bin/ruby
STDOUT.sync = true
puts 'before "system" ctrl-c stops the script immediately'
STDIN.sysread(1)
  # intTrap = trap 'INT', 'DEFAULT' # ---------------------- if uncomment this wrapper
system 'echo blabla'
  # trap 'INT', intTrap # ---------------------------------- then ctrl-c works immediately
puts 'but after "system" ctrl-c waits until I press Enter'
STDIN.sysread(1)


--- output ---

$ ./x.rb
before "system" ctrl-c stops the script immediately
./x.rb: Interrupt

$ ./x.rb
before "system" ctrl-c stops the script immediately

blabla
but after "system" ctrl-c waits until I press Enter
I'm pressing ctrl-c right now... but it stops only after Enter
./x.rb: Interrupt




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