Fortran 90 provides for an "ADVANCE" option for WRITE commands. Specifying an ADVANCE='NO' suppresses this carriage return/line feed so that the input is entered on the same line as the prompt.
Entering the command
will utilize this option to suppress the carriage return/line feed after printing the prompt character.
This feature is compiler dependent. Some Fortran compilers do not support the ADVANCE option when writing to standard output. Specifcally, the Intel Fortran compiler used for the Microsoft Windows implementation does not support this (note that earlier versions of this compiler did support support this). The gfortran compiler used for Linux/Unix and Mac OS X implementations does support this feature.
SET PROMPT ADVANCE OFF
PROBE PROMPT ADVANCE
SET PROMPT ADVANCE ON