Thanks Jürgen for correcting my comment. You've prompted me to browse through my venerable copy of Josuttis' The C++ Standard Library. respect…
Peter On 2014-06-01, at 8:00 AM, Juergen Sauermann <[email protected]> wrote: > Hi Peter, > > almost correct. The first comment should be "// may point to an optional > string typically containing 6 spaces". > prompt can be 0 and then no prompt is printed. Otherwise the function pushes > the prompt (backwards) > back into stdin. Whether that works is a matter of the underlying operating > system. The man page > of ungetc() says that only 1 ungetc() char is guaranteed but we push 6. > Another question is whether > an ungetc() into stdin will occur on C++ cin? > > The main use case for this were scripts where it does not matter too much if > a prompt is printed > or not. Note also that pushing chars back into stdin has a different effect > than just printing the prompt > - there are cases where the prompt should be editable (⍞ I believe). > > /// Jürgen
