#!/usr/bin/ruby

# mpipe reads STDIN and pipes it to multiple processes
#
# Usage: whatever | rpipe.rb -pipe pgm1 -pipe pgm2 -p 1 -d toto -pipe pgm3 -x
#
# pgm1, pgm2 and pgm3 will all receive whatever's STDOUT on their STDIN
#
# Current limitation: programs that expect a -pipe argument themselves cannot be called
#
# Target usage: send CVS loginfo to multiple processes

# Look for -pipe ... in ARGV

aPipes=[]
curr=""
ARGV.each {|p|
  if p == '-pipe'
    # We have got a pipe cmd
    aPipes << IO.popen(curr, "w") if curr.length > 0
    # Start next pipe
    curr=""
  else
    curr << p << " " # Add argument to current pipe cmd
  end
}
# Last cmd
aPipes << IO.popen(curr, "w") if curr.length > 0

# Read STDIN and send it to all opened pipes
STDIN.each { |line|
  aPipes.each { |p|
    p.puts(line)
  }
}

# Close all pipes and exit
aPipes.each {|p| p.close_write}