I've ... included $! in die.

You've only done half the job there :-). If you don't put both the filename and the OS error in the error message, the user can't diagnose the actual problem. OP's (unhelpful) error message: 

Could not open file

[download]
Your (fractionally more helpful) error message: 
Could not open file: Permission denied

[download]
This: 
open(my $FILEHANDLE, ">", $filename)
    or die "Cannot open $filename: $!";

[download]
yields a helpful error message: 
Cannot open /dev/secret: Permission denied

[download]
To be super-picky, it's "Cannot open", not "Can't open", or "Could not open", or any other variation. In English, at least.

In reply to Re^2: Sending filehandles? by djp
in thread Sending filehandles? by tamaguchi

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