Hi, I was trying to extract the following words (b and f sentence - b should only be from f sentence ) from input file. But I'm not sure what's the correct regex for the following codes.Sorry about that, I have edited the output description.

My code : 

open (INPUT, "<", $ARGV[0]) || die "\nError: File Read \"$ARGV[0]\"\nE
+rror: $!\n\n"; 

while ( $line = <INPUT> ) {
  if ( $line =~ /^(b|f)/) {
    print $line;
  }
}
close INPUT;

[download]

Input file : (to extract for b and f)

b=23 y=0x11 arg=0x70 def=0x1 val=0x234
checking system

b=71 y=0x35 arg=0x87 def=0x3 val=0x76d
h=reg.k2.io.chk 0x2001

b=54 y=0x23 arg=0x78 def=0x2 val=0x65b
f chk.fin.reg.m_cwr 0x213

b=54 y=0x23 arg=0x78 def=0x2 val=0x65b
checking system

b=40 y=0x90 arg=0x34 def=0x5 val=0x2197
f ref.grf.pin.clk_trg 0x0021

[download]

Expected output: 

b=54 y=0x23 arg=0x78 def=0x2 val=0x65b
f chk.fin.reg.m_cwr 0x213
b=40 y=0x90 arg=0x34 def=0x5 val=0x2197
f ref.grf.pin.clk_trg 0x0021

The b must be from f 
From the b and f I want to get the from b (y, arg and def) 
and f (\w+ - chk.fin.reg.m_cwr /ref.grf.pin.clk_trg )

[download]

2018-03-12 Athanasius added code and paragraph tags

In reply to perl regex for repeating words by analys

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