s command asks for filename even when it knows it will reject it

[subrook]

As documented in less 551, the s command "only works if the input is a pipe, not an ordinary file." However, when viewing an ordinary file, typing s gives the prompt log file: and accepts a filename. Only after the filename is entered does it say Input is not a pipe. There is no need to prompt for and allow the user to enter a filename that will only be rejected; whether input is a pipe is known the moment the user presses s.

[gwsw]

Good point. This is fixed in c25faac.