FORTRAN Reference Manual

FORTRAN Reference Manual—528615-001

5-1

Introduction to File I/O in the

HP NonStop Environment

This section introduces FORTRAN I/O in the HP NonStop environment. Topics covered

in this section include:

FORTRAN I/O Statements

FORTRAN I/O statements include data transfer statements, file status statements, and

file positioning statements. Table 5-1 summarizes FORTRAN I/O statements. For a

detailed description of each statement, see Section 7, Statements.

Data transfer statements direct the transfer of data between internal storage and

external media or internal files. Data transfer statements include:

•

Formatted READ, WRITE, and PRINT statements

•

Unformatted READ and WRITE statements

•

List-directed READ, WRITE, and PRINT statements

File status statements, OPEN, CLOSE, and INQUIRE, determine the properties of the

connection to the external medium.

Topic Page

FORTRAN I/O Statements

5-1

Records 5-2

FORTRAN Files 5-3

Units 5-8

File Characteristics 5-16

Control Specifiers in I/O Statements 5-24

I/O Lists 5-26

Unformatted I/O 5-28

Formatted I/O 5-28

I/O Performance 5-31

Table 5-1. FORTRAN I/O Statements (page1of2)

Name Action

BACKSPACE Positions file just before the preceding record.

CLOSE Disconnects file from unit.

ENDFILE Writes an end of file record as the next record of a file.