ooh thanks BrowserUk never eard of -p operator, or may be forgotten it long time ago.
Due to my ignorance i wonder if -p -t are one the opposite of the other: in the docs -p is just mentioned and, albeit self explanatory, not described. There are cases where -t does not suffice, are also cases where -p does not suffice? edge cases?
My test:

perl -e " print -t STDIN ? qq(STDIN has tty) : qq(NO tty associated);p
+rint ' - '; print -p STDIN ? qq(STDIN is a pipe or a named pipe) : qq
+(NOT a pipe)"

#out
#STDIN has tty - NOT a pipe


hostname | perl -e " print -t STDIN ? qq(STDIN has tty) : qq(NO tty as
+sociated);print ' - '; print -p STDIN ? qq(STDIN is a pipe or a named
+ pipe) : qq(NOT a pipe)"

#out
#NO tty associated - STDIN is a pipe or anamed pipe
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thanks
L*