Specifying options on the command line

XL Fortran supports the traditional UNIX method of specifying command-line options, with one or more letters (known as flags) following a minus sign:

  xlf95 -c file.f

You can often concatenate multiple flags or specify them individually:

  xlf95 -cv file.f     # These forms
  xlf95 -c -v file.f   # are equivalent

(There are some exceptions, such as -pg, which is a single option and not the same as -p -g.)

Some of the flags require additional argument strings. Again, XL Fortran is flexible in interpreting them; you can concatenate multiple flags as long as the flag with an argument appears at the end. The following example shows how you can specify flags:

# All of these commands are equivalent.
  xlf95 -g -v -o montecarlo -p montecarlo.f
  xlf95 montecarlo.f -g -v -o montecarlo -p
  xlf95 -g -v montecarlo.f -o montecarlo -p
  xlf95 -g -v -omontecarlo -p montecarlo.f
# Because -o takes a blank-delimited argument,
# the -p cannot be concatenated.
  xlf95 -gvomontecarlo -p montecarlo.f
# Unless we switch the order.
  xlf95 -gvpomontecarlo montecarlo.f

You can also specify many command-line options in a form that is intended to be easy to remember and make compilation scripts and makefiles relatively self-explanatory:

>>- -q--option_keyword--+---------------------------------------+-><
                        |    .-:------------------------------. |   
                        |    V                                | |   
                        '-=----suboption--+-----------------+-+-'   
                                          |    .-,--------. |       
                                          |    V          | |       
                                          '-=----argument-+-'       

This format is more restrictive about the placement of blanks; you must separate individual -q options by blanks, and there must be no blank between a -q option and a following argument string. Unlike the names of flag options, -q option names are not case-sensitive except that the q must be lowercase. Use an equal sign to separate a -q option from any arguments it requires, and use colons to separate suboptions within the argument string.

For example:

 xlf95 -qddim -qXREF=full -qfloat=nomaf:rsqrt -O3 -qcache=type=c:level=1 file.f