Guardian Procedure Calls Reference Manual

BACKSPACEEDIT Procedure
Summary
Syntax for C Programmers
Syntax for TAL Programmers
Parameters
Returned Value
Related Programming Manual
Summary
The BACKSPACEEDIT procedure sets the current record number of an IOEdit file to that of the line
preceding what was the current record before the call. These rules describe the operation of
BACKSPACEEDIT:
• If the current record number is -1 (which occurs when the file is empty or when the file is
positioned at the beginning, as when it is just opened), BACKSPACEEDIT does nothing.
• If the current record number is -2 (which occurs when the current record number has been
incremented beyond the last record in the file), the current record number is set to the highest
record number in the file. If the file is empty, the current record number is set to -1.
• If the current record number is zero (0) or greater, the current record number is set to the
highest record number in the file that is less than the current record number before the call; if
there is no such record, the current record number is set to -1.
BACKSPACEEDIT is an IOEdit procedure and can only be used with files that have been opened
by OPENEDIT or OPENEDIT.
Syntax for C Programmers
#include <cextdecs(BACKSPACEEDIT)>
short BACKSPACEEDIT ( short filenum );
Syntax for TAL Programmers
error := BACKSPACEEDIT ( filenum ); ! i
Parameters
filenum
input
INT:value
is the number that identifies the open file on which the operation is to be performed.
Returned Value
INT
A file-system error code that indicates the outcome of the call.
Related Programming Manual
For programming information about the BACKSPACEEDIT procedure, see the Guardian
Programmer's Guide.
BACKSPACEEDIT Procedure 85