Hi, I want to dynamically create the format of the printf function. I want to create a "printToFile" function that can be dynamic, so that it can handle any number of given arguments to write to the file, in the specified format.

I have this code:

sub printfToFile {
  my $file = shift;
  my $format = shift;
  my $arrayCount = @_;
  
  my $formatString;
  
  for (my $r = 1;$r <= $arrayCount; $r++) {
      $formatString = $formatString.'$format ';
  }
  
  $formatString = trim( $formatString );
  $formatString = $formatString.'\n';
  
  open IO, ">>$file" or die "Cannot open $file for output: $!\n+";
#  printf IO "$format $format\n", @_;
  printf IO "$formatString", @_;
  close IO;
}

[download]

The commented out line works perfectly, the printf function will write the 2 strings in the file, with the $format that I specified when calling the function

printfToFile( $logfile, '%-22s', $ifName, $ifLease );

[download]

Now, I want to dynamically create that format line, and with the previous code, the $formatString value is identical to this: $format $format\n

Why would printf print this to the file: $format $format\n$format $format\n, etc.

Thank you very much!

In reply to Interpret a string that contains strings by bArriaM

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