#!/usr/bin/perl

# Routine to correct the syntax error in the NNSN FITS headers that list
# "A'HEARN" in the submitter field, as identified in the "ahearn.sub" file.
# We'll need to fix just the FITS headers for these files.  Fortunately,
# the corrected SUBMITTR line is identical in all cases.
#
# Format: % fixmasub

$TMPFILE = "__bob.tmp";

# First, we'll set the corrected line:

$newsub = sprintf "%-80.80s", 
                  "SUBMITTR= 'A''HEARN,M        ' /submitter's name";

# Now we'll loop through the list of files to be corrected (this list has the
# path information):

open (LST,"ahearn.sub")  ||  die "Could not open 'ahearn.lst' ($!)";

while ($file=<LST>)
  { chop $file;
    $filename = substr($file,12,8);

    # We'll start with the FITS file.  We know the SUBMITTR line is the 16th
    # in the first FITS block.

    open (TMP,">$TMPFILE")  ||  die "Could not open $TMPFILE ($!)";
    open (FIT,$file)  ||  die "Could not open $file ($!)";

    read FIT,$block,2880;
    substr($block,1200,80) = $newsub;
    syswrite TMP,$block,2880;

    # Now just copy the rest of the file:

    while (!eof(FIT))
      { read FIT, $block, 2880;
        syswrite TMP, $block, 2880;
      }
    close(FIT);
    close(TMP);

    rename $TMPFILE, $file;
  }