Open Watcom FORTRAN 77 Language Reference

FORTRAN Statements
3. A character substring name.
4. An array name except an assumed-size dummy array.
5. An implied-DO list of the form:
( dlist, i = e1, e2 [,e3] )
where dlist is composed of one or more of items (1) through (5).
Example:
READ( 5, 100 )X, Y, Z
READ( UNIT=5, FMT=100 )X, Y, Z
100 FORMAT( 3F10.5 )
READ( UNIT=5, FMT=’( 3F10.5 )’ )X, Y, Z
READ( 5, ’( 3F10.5 )’ )X, Y, Z
The above gives four examples of formatted READ statements, using the first of three supported forms of
the READ statement. In all cases, the format conversion is identical but it was specified in different ways.
When executed, the effect of all READ statements is the same. The unit number that is explicitly used in
this form of the READ statement is unit number 5. There are, in fact, many other ways in which the READ
statement could have been written, all of which would have the same effect when executed. We have not
shown the use of all the specifiers.
Example:
READ 100, X, Y, Z
100 FORMAT( 3F10.5 )
READ ’( 3F10.5 )’, X, Y, Z
The above gives two examples of formatted READ statements, using the second of three supported forms of
the READ statement. In both cases, the format conversion is identical but it was specified in different ways.
When executed, the effect of both READ statements is the same. The unit number that is implicitly used in
this form of the READ statement is unit number 5.
Example:
READ( 5, * )X, Y, Z
READ( *, * )X, Y, Z
READ( UNIT=5, FMT=* )X, Y, Z
READ( UNIT=*, FMT=* )X, Y, Z
READ *, X, Y, Z
READ , X, Y, Z
The above six examples of list-directed formatted input are all equivalent. Open Watcom FORTRAN 77
assumes unit 5 when the unit number identifier is an asterisk (as in the second and fourth examples). In the
fifth example, the asterisk is a format identifier indicating list-directed formatting. The fifth and sixth
examples are examples of the second and third forms, respectively, of the READ statement in which Open
Watcom FORTRAN 77 assumes unit 5. When the format identifier is an asterisk or when the third form of
the READ statement is used, we call this list-directed list-directed formatting.
READ Statement 125