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CHAPTER
1
Fortran Library Routines
This chapter describes the Fortran library routines alphabetically. See the
FORTRAN 77 Language Reference for details on Fortran 77 and VMS intrinsic
functions. All the routines described in this chapter have corresponding man pages
in section 3F of the man library. For example, man -s 3F access will display the
man page entry for the library routine access.
See also the Numerical Computation Guide for additional math routines that are
callable from Fortran and C. These include the standard math library routines in
libm and libsunmath (see Intro(3M)), optimized versions of these libraries, the
SPARC vector math library, libmvec, and others.
Data Type Considerations
Unless otherwise indicated, the function routines listed here are not intrinsics. That
means that the type of data a function returns may conflict with the implicit typing
of the function name, and require explicit type declaration by the user. For example,
getpid() returns INTEGER*4 and would require an INTEGER*4 getpid
declaration to ensure proper handling of the result. (Without explicit typing, a REAL
result would be assumed by default because the function name starts with g.) As a
reminder, explicit type statements appear in the function summaries for these
routines.
Be aware that IMPLICIT statements and the -r8, -i2, -dbl and -xtypemap
compiler options also alter the data typing of arguments and the treatment of return
values. A mismatch between the expected and actual data types in calls to these
library routines could cause unexpected behavior. Options -r8 and -dbl promote
the data type of INTEGER functions to INTEGER*8, REAL functions to REAL*8, and
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