FORTRAN Reference Manual

Statements

FORTRAN Reference Manual—528615-001

7-15

CHECKPOINT Statement

The CHECKPOINT statement establishes a takeover point for a backup process, or

transfers the data and environment information needed by the backup process to take

over, or both. CHECKPOINT is an HP extension to the ANSI standard.

CHECKPOINT enables you to use the HP fault-tolerant programming facility.

unit

is an integer expression having a value ranging from 1 through 999 that identifies

the number of a FORTRAN unit whose status is to be checkpointed. You can

specify any number of units in one CHECKPOINT statement.

cpt-spec

is one of the following:

FILENUM = exp

exp is an integer expression whose value is the Guardian file number of a file

whose status is to be checkpointed. You can specify any number of files in one

CHECKPOINT statement.

ERR = label

label is the label of an executable statement in the current program unit to

which FORTRAN transfers control if an error occurs while executing the

CHECKPOINT statement.

BACKUPSTATUS = status

status is an integer variable in which FORTRAN returns the status of the

backup process after executing the CHECKPOINT statement. Table 7-10 on

page 7-102 lists the status codes that can be returned to your program after it

executes a CHECKPOINT or START BACKUP statement. Status codes

greater than or equal to 1000 indicate that the backup was not successfully

started.

STACK = stack

stack is a character expression whose value (ignoring any trailing blanks) is

either 'YES' or 'NO'. The default value is 'YES'. See Considerations.

CHECKPOINT

[ data [, data ]... ]

UNIT=[]unit , UNIT=unit

[]. . . , cpt spec–[]. . . ()

cpt spec , cpt spec–[]. . .–()