Fstat

fstat is a numeric status that is returned upon execution of a database operation, a sequential file operation, or a lock instruction.

Syntax

fstat

Examples

# MYTABLE is a table with a key called KEY1, that has a unique component called KEYVAL
# Create a record in the table MYTABLE with they key value 1 if it doesn't exist 
Local File MYTABLE [MYT]
Read [MYT]KEY1=1
If fstat
   [MYT]KEYVAL=1 : Write [MYT]
   If fstat
      MSG="The key was created in the mean time"
   Else
      MSG="Key created"
   Endif
Else
   MSG="Key already exists"
Endif

Details

fstat is always set to '0' if the operation is successfully completed, and has a non-null value if there is an error:

• In a sequential read (Getseq and Rdseq), fstat is set to '1' at the end of the file.
• On Lock, fstat is set to '1' if the lock could not be performed.
• For a database operation (Read, Look, Readlock, For, Write, Delete, Rewrite, DeleteByKey, and RewriteByKey), the error statuses are from 1 to 7, as shown in the following table.

Note that the use of literal numbers should be avoided: dedicated constants exist for this purpose.

Constant	Value	Explanation
[V]CST_AOK	0	Operation succeeded.
[V]CST_ALOCK	1	Record is locked.
[V]CST_AOUTSEARCH	2	In <= or >= read mode, indicates that read succeeded, but the key found is not equal to the value.
[V]CST_ADUPKEY	3	Duplicate value on unique index.
[V]CST_AOUTKEYS	4	Attempt of reading a key value that is smaller or greater than all existing key values.
[V]CST_ANOREC	5	Record not read (no current record exists).
[V]CST_ARECTICKUPD	6	Update conflict: the line no longer exists with the right updtick value (concurrency error during an update operation).
[V]CST_ARECTICKDEL	7	Delete conflict: The line no longer exists with the right updtick value (concurrency error during a delete operation).

See also

Getseq, Rdseq, Lock, Read, Look, Readlock, For, Write, Delete,Rewrite, DeleteByKey, RewriteByKey.