Why is 'more' giving the 'next file' prompt?

[Richard Tobin]

In article <1990May3.160744.25250 at bath.ac.uk> exspes at bath.ac.uk (P E Smee) writes:
>   cat fred | csh -c 'cat >tempxxx ; more tempxxx'
>
>Before 'more' puts anything out, it gives the 'Next file (tempxxx):'
>prompt.  

Try these:

more /etc/group < /etc/group
more /etc/group < /dev/null
more /etc/group < /dev/tty

It seems that rather than reading its standard input only if no file
arguments are given, more read its standard input unless it's a terminal.
My Sun manual doesn't document this.

-- Richard
-- 
Richard Tobin,                       JANET: R.Tobin at uk.ac.ed             
AI Applications Institute,           ARPA:  R.Tobin%uk.ac.ed at nsfnet-relay.ac.uk
Edinburgh University.                UUCP:  ...!ukc!ed.ac.uk!R.Tobin