XL Fortran Enterprise Edition for AIX : User's Guide - IBM

Note: You may need the old setting to read existing data files that contain
NAMELIST output.However, use the standard-compilant new format in
writing any new data files.
With namelist=old, the nonstandard NAMELIST format is not considered an
error by the langlvl=95std, langlvl=90std, or langlvl=2003std setting.
Related Information: For more information about NAMELIST I/O, see
Namelist Formatting in the XL Fortran Enterprise Edition
for AIX Language Reference.
nlwidth=record_width
By default, a NAMELIST write statement produces a single output record long
enough to contain all of the written NAMELIST items. To restrict NAMELIST
output records to a given width, use the nlwidth run-time option.
Note: The RECL= specifier for sequential files has largely made this option
obsolete, because programs attempt to fit NAMELIST output within the
specified record length. You can still use nlwidth in conjunction with
RECL= as long as the nlwidth width does not exceed the stated record
length for the file.
random={generator1 | generator2}
Specifies the generator to be used by RANDOM_NUMBER if
RANDOM_SEED has not yet been called with the GENERATOR argument.
The value generator1 (the default) corresponds to GENERATOR=1, and
generator2 corresponds to GENERATOR=2. If you call RANDOM_SEED with
the GENERATOR argument, it overrides the random option from that point
onward in the program. Changing the random option by calling SETRTEOPTS
after calling RANDOM_SEED with the GENERATOR option has no effect.
scratch_vars={yes | no}
To give a specific name to a scratch file, set the scratch_vars run-time option to
yes, and set the environment variable XLFSCRATCH_unit to the name of the
file you want to be associated with the specified unit number. See “Naming
Scratch Files” on page 332 for examples.
unit_vars={yes | no}
To give a specific name to an implicitly connected file or to a file opened with
no FILE= specifier, you can set the run-time option unit_vars=yes and set one
or more environment variables with names of the form XLFUNIT_unit to file
names. See “Naming Files That Are Connected with No Explicit Name” on
page 331 for examples.
uwidth={32 | 64}
To specify the width of record length fields in unformatted sequential files,
specify the value in bits. When the record length of an unformatted sequential
file is greater than (2**31 - 1) bytes minus 8 bytes (for the record terminators
surrounding the data), you need to set the run-time option uwidth=64 to
extend the record length fields to 64 bits. This allows the record length to be
up to (2**63 - 1) minus 16 bytes (for the record terminators surrounding the
data). The run-time option uwidth is only valid for 64-bit mode applications.
xrf_messages={yes | no}
To prevent programs from displaying run-time messages for error conditions
during I/O operations, RANDOM_SEED calls, and ALLOCATE or
DEALLOCATE statements, set the xrf_messages run-time option to no.
Otherwise, run-time messages for conversion errors and other problems are
sent to the standard error stream.
58 XL Fortran Enterprise Edition for AIX : User’s Guide