channel 0
45464
46577
45213
4878734
...

channel 1
57767
76746
746479
43446
...

my $file = '/Pfad/zur/datei.txt';
my $result = `grep -c "^channel" $file`; # Backticks
chomp $result;
print "Es sind $result Kanaele\n";

#!/usr/bin/perl
#require 'ctime.pl';
use POSIX qw(strftime);

$in = $ARGV[0];


open ( IN, "<$in") || die "ERROR, can't open $in";

sub getcfg()
{
  while ( <IN> ){
    if ( $_ =~ /\[adudata.*\]/){
      return 0;
    }
    if ( $_ =~ /starttime=.*/){
      @starttime= split ("=",$_);
    }
    if ( $_ =~ /iSampleRate=.*/){
      @iSampleRate= split ("=", $_);
    }
    if ( $_ =~ /szLabel=.*/){
      @szLabel= split ("=", $_);
    }
    if ( $_ =~ /SensUnit=.*|MeasUnit=.*/){
      @SensUnit= split ("=", $_);
    }
    if ( $_ =~ /startPtime=.*/){
      @startPtime= split ("=", $_);
    }
    if ( $_ =~ /iSampleRate=.*/){
      @iSampleRate=split ("=", $_);
    }
    if ( $_ =~ /iChGroup=.*/){
      @iChGroup=split ("=", $_);
    }
    if ( $_ =~ /iRPMChannel=.*/){
      @iRPMChannel=split ("=", $_);
    }
  }
};

sub printdata()
{
  while ( <IN> )
  {
    #test auf zahl
    if ($_ =~ /^([+-]?\d+(\.\d+)?([Ee][+-]?\d+)?)/ ){
      print OUT "$_";
    }
    else{
      return 0;
    }
  }
};


sub printheader()    #An dieser Stelle soll abgefragt 
        #werden wieviele channels es gibt.
{            
  printf (OUT "ch $ch[1]"."\n");
  while ( <IN> )
  {
    $anz = `grep -c "^aduchannel" $_`;
    chomp $anz;
    printf (OUT "number of channels $anz"."\n")
  }
  printf (OUT "Samplerate $iSampleRate[1]");
  printf (OUT "divided by Gain 1  "."\n");
};


while ( <IN> )
{


    if ( $_ =~ /\[aduchannel.*\]/ ){
        chop;chop;
        @ch= split ("aduchannel",$_);
        $zeile= $ARGV[0];
        @name= split ('-',$zeile);
        $out = sprintf ("%s_ch%d.txt", $name[0] , $ch[1] , $szLabel[1] );
        &getcfg();
        $timestr=strftime("%Y%m%d-%H.%M",localtime($starttime[1]));
        $out = $name[0]."_".$timestr."_ch".$ch[1]."_".$szLabel[1].".txt";
        open ( OUT, ">$out" ) || die "ERROR, can't open $out";
        }



    if ( $_ =~ /\[adudata$ch[1]\]/ ){
        &printheader();
        &printdata();
    }


}


close IN;
close OUT;