[J3] EOF not detected

[Van Snyder]

To save space I gzip-compressed a large number of data files.

Then to read them I create a FIFO (if it doesn't already exist):

inquire ( file='MyFifo', exist=exist )
if ( .not. exist ) call execute_command_line ( 'mkfifo MyFifo' )

open the FIFO, and start another process to decompress them:

call execute_command_line ( 'zcat ' // trim(file) //  '> MyFifo ' )

The END= exit in the read statement isn't taken.

So I changed the code to detect "EOF" and pretend it's the end of file,
and instead do

call execute_command_line ( 'zcat ' // trim(file) //  '> MyFifo ; echo
EOF > MyFifo' )

or

call execute_command_line ( '(zcat ' // trim(file) //  ; echo EOF) '>
MyFifo ' )

"gunzip" can uncompress the files in one second.

The program processes uncompressed files in about two seconds.

Reading and processing the compressed files using the above methods
takes 25 seconds.

I also tried appending EOF to the files before compressing them and
then reading them using the first method, with the same result.

(1) Why does END= not branch when reading from a FIFO?

(2) Why does it run so much longer when reading from a FIFO?

(all of this with ifx (IFX) 2025.2.1 20250806; I haven't tried it yet
with gfortran or nagfor).
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