fpt Reference: CHANGE DEFINE FILE TO OPEN

fpt and WinFPT Reference Manual - Command-line Commands

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CHANGE DEFINE FILE TO OPEN

Syntax:

[DO NOT] CHANGE DEFINE FILE TO OPEN

Function:

The DEFINE FILE statement specifies the attributes of an unformatted direct access file. The syntax is:

DEFINE FILE <lun>(<nrec>,<recl>,U,<asvar>)

where:

<lun> is the logical unit number of a file to be opened
<nrec> is the number of records in the file
<recl> is the record length
U is a keyword which must always be U and must always be present
<asvar> is an associated integer variable which is incremented whenever the file is read or written.

<lun>, <nrec>, and <recl> may be literal integer values, integer Fortran parameters or integer variables. Each must be represented by a single token. They may not be expressions or array elements. The <recl> argument is measured in 16-bit units.

The statement is almost equivalent to:

OPEN (UNIT=<lun>, STATUS='UNKNOWN', ACCESS='DIRECT', FORM='UNFORMATTED', RECORDTYPE='FIXED', MAXREC=<nrec>, RECL=((<recl>+1)/2), ASSOCIATEVARIABLE=<asvar>)

The difference is that DEFINE FILE does not immediately open the file. It is opened when it is first read or written to.

This command comments out the original DEFINE FILE statement and writes a translation to an OPEN statement after it. The MAXREC argument is omitted.

Where to Use this Command

Operating system command line	Yes
Configuration file, config.fsp	Yes
Specification (fsp) files, *.fsp	Yes
Interactively, to FPT> prompt	Yes *
Interactive command files	Yes *
Embedded in the Fortran code	Yes

* If the command is made interactively and any of the commands CHANGE ALL IO TO SUBPROGRAM CALLS, CHANGE FILE IO TO SUBPROGRAM CALLS or CHANGE ISAM FILE REFERENCES TO SUB-PROGRAM CALLS is used the command CHANGE DEFINE FILE TO OPEN should be made first.

Default

No change is made by default.

Example

The original code:

DEFINE FILE 8(2000,24,U,iav)

is translated to:

!!! FPT DEFINE FILE 8(2000,24,U,iav) OPEN(UNIT=8, STATUS='UNKNOWN', ACCESS='DIRECT', FORM='UNFORMATTED', & RECORDTYPE='FIXED', RECL=24, ASSOCIATEVARIABLE=iav)

Thanks

Thanks are due to James Hale and Denys Beauchemin at Sector7 Inc. who found this little horror.