Thanks for your replies,

when executing this in iterm..

perl -i -pe'
  BEGIN { $/ = "}\n" }
  s/@{[ <<REGEX ]}/@{[ <<STRING ]}/g;
if ((!(\$session_login)) or (\$session_access < 5)) { 
header("Window-Target: _top"); 
header("Location: index.php"); 
}
REGEX
if ((!(\$session_login)) or (\$session_access < 5)) { 
header("Window-Target: _top"); 
header("Location: index.php"); 
exit;
}
STRING
' *.php
[download]

I get back the following error messages
Can't find string terminator "REGEX" anywhere before EOF at -e line 3.
-bash: BEGIN: command not found
-bash: s/@{[: No such file or directory
I am probly missing something obvious, due to no EOF usage experience.
Any help on these err messages is greatly appreciated!