So the answer here is that I have to open "/dev/tty" each time I call it rather than reference my already-open "STDOUT"?

I don't have linux, but no, I don't think that is the answer.

I think part of the answer is to do error checking correctly like the faq entry

I also think using S4 is part of the answer, not being an expert on pack/unpack and not having a /dev/tty, I can't run any tests.

Hmmm....I'm disappointed that I need to open another file handle and can't get the rows & columns associated with my already open FH, "STDOUT", directly...

Sounds premature if you ask me, avoiding abstractions always involves some growing pains :)

Shouldn't STDIN, STDOUT map to fd[0], fd[1] => /dev/pts/1 on some level?

They do 

$ perl -le " print fileno($_) for STDIN, STDOUT, STDERR "
0
1
2

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See, fd 0,1,2. Now regarding tty, using operator -t to test if filehandle is opened to a tty, you can see 0,1,2 are connected to a tty 
$ perl -le " print 0+-t $_  for STDIN, STDOUT, STDERR "
1
1
1

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but not when you do redirection, here is STDIN not connected to a tty 
$ perl -le " print 0+-t $_  for STDIN, STDOUT, STDERR "  < NUL
0
1
1

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here is STDIN and STDERR not connected to a tty 
$ perl -le " print 0+-t $_  for STDIN, STDOUT, STDERR "  < NUL  2> NUL
0
1
0

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here is STDOUT not connected to a tty 
$ perl -le " print 0+-t $_  for STDIN, STDOUT, STDERR " > out.txt

$ cat out.txt
1
0
1

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I.e. Shouldn't I be able to use some mapping function on STDOUT to get a file descriptor that's suitable for ioctl?

ioctl says you don't need to, the faq item doesn't, and neither does Term::Size::Any

In reply to Re^3: Failing to get current TTY's rows & columns... by Anonymous Monk
in thread Failing to get current TTY's rows & columns... by perl-diddler

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