perl -i.one -le 'chomp( my @cinfo= <> ); $cinfo[1]=0; print @cinfo' *.txt
perl -i.one -e 'my @cinfo= <>; $cinfo[1]= "0\n"; print @cinfo' *.txt
perl -i.one -nle 'print 2==$. ? 0 : $_' *.txt
perl -i.one -ple '$_= 0 if 2==$.' *.txt
perl -i.one -pe '$_= "0\n" if 2==$.' *.txt