LF95 Linux User's Guide - Lahey Computer Systems

Appendix A Programming Hintsfloating-point data can be accommodated with runtime options C and M (see “RuntimeOptions” on page 131). By default, LF64 reads and writes numeric data in “little-endian”format.File Creation: Default NamesIf a file is opened without specifying a filename, the file is assigned the name fort.unit,where unit is the unit number specified in the OPEN statement.If a file is opened as STATUS=’SCRATCH’, and FILE= is not specified, then the file isassigned a random name and is created in the system temporary directory. If FILE= is specified,then the file is created in the current working directory. In both cases, the file is deletedupon program termination, even if it is closed with STATUS=’KEEP’ (see “IntermediateFiles” on page 13).Normal program termination causes all files to be closed.Link TimeYou can reduce the link time by reducing the number of named COMMON blocks you use.Instead of coding:code:common /a1/ icommon /a2/ jcommon /a3/ k...common /a1000/ k1000common /a/ i,j,k, ..., k1000Year 2000 complianceThe "Year 2000" problem arises when a computer program uses only two digits to representthe current year and assumes that the current century is 1900. A compiler can look for indicationsthat this might be occurring in a program and issue a warning, but it cannot foreseeevery occurrence of this problem. It is ultimately the responsibility of the programmer to correctthe situation by modifying the program. The most likely source of problems for Fortranprograms is the use of the obsolete DATE() subroutine. Even though LF64 will compile andlink programs that use DATE(), its use is strongly discouraged; the use ofDATE_AND_TIME(), which returns a four digit date, is recommended in its place.126 Lahey/Fujitsu Linux64 Fortran User’s Guide