| Navigation: Language Reference > 13 - Built-in Functions >====== BYTES (return size in bytes) ====== |    |
BYTES(file)
| BYTES | Returns number of bytes in FILE, or most recently read. |
| file | The label of a FILE. |
The BYTES procedure returns the size of a FILE in bytes or the number of bytes in the last record successfully accessed. Following an OPEN statement, BYTES returns the size of the file. file{PROP:FileSize} is equivalent to BYTES after a file open and will also return the size of the file. After the file has been successfully accessed by GET, REGET, NEXT, PREVIOUS, ADD, or PUT, the BYTES procedure returns the number of bytes accessed in the RECORD. The BYTES procedure may be used to return the number of bytes read in a variable length record.
In SQL tables, if BYTES(file) is used before the file is opened, then it returns the number of rows in the table. If it is used after the file is opened and a successful record retrieval, it returns the number of bytes in the record buffer.
BYTES() return a negative value for files greater than 2Gb and less than 4Gb. Assigning the result to a ULONG gives the correct positive value of file size.
| Return Data Type: | LONG |
Example:
DosFileName STRING(260),STATIC
LastRec LONG
SavPtr LONG(1) !Start at 1
FileSize LONG
DosFile FILE,DRIVER('DOS'),PRE(DOS),NAME(DosFileName)
Record RECORD
F1 STRING(2000)
END
END
BlobStorage FILE,DRIVER('TopSpeed'),PRE(STO)
File BLOB,BINARY
Record RECORD
FileName STRING(64)
END
END
CODE
IF NOT FILEDIALOG('Choose File to Store',DosFileName,,0010b)
RETURN
END
OPEN(BlobStorage) !Open the BLOB file
STO:FileName = DosFileName !and store the filename
OPEN(DosFile) !Open the file
FileSize = BYTES(DosFile) !Get size of file
STO:File{PROP:Size} = FileSize !and set the BLOB to store the file
LastRec = FileSize % SIZE(DOS:Record) !Check for short record at end of file
LOOP INT(FileSize/SIZE(DOS:Record)) TIMES
GET(DosFile,SavPtr) !Get each record
ASSERT(NOT ERRORCODE())
!String slice data into BLOB:
STO:File[SavPtr - 1 : SavPtr + SIZE(DOS:Record) - 2] = DOS:Record
SavPtr += SIZE(DOS:Record) !Compute next record pointer
END
IF LastRec !If short record at end of file
GET(DosFile,SavPtr) !Get last record
ASSERT(BYTES(DosFile) = LastRec) ! size read should match computed size
STO:File[SavPtr - 1 : SavPtr + LastRec - 2] = DOS:Record
END
ADD(BlobStorage)
ASSERT(NOT ERRORCODE())
CLOSE(DosFile);CLOSE(BlobStorage)
See Also: