Last modified: Fri Feb 11 14:23:42 2005.
NAME:
Open_Binary_File
PURPOSE:
Function to open the unformatted, sequential access Binary files
CALLING SEQUENCE:
Error_Status = Open_Binary_File( Filename, & ! Input
FileID, & ! Output
For_Output = For_Output, & ! Optional input
No_Check = No_Check, & ! Optional input
Message_Log = Message_Log ) ! Error messaging
INPUT ARGUMENTS:
Filename: Name of the Binary file to open.
UNITS: N/A
TYPE: CHARACTER(*)
DIMENSION: Scalar
ATTRIBUTES: INTENT( IN )
OPTIONAL INPUT ARGUMENTS:
For_Output: Set this optional argument to open a new file for
writing. Default action is to open an existing file
for read access. Note, if the file already exists and
it is opened with this keyword set, the file is
overwritten.
If == 0, existing file is opened for READ access (DEFAULT)
ACTION='READ', STATUS='OLD'
== 1, new file is opened for WRITE access.
ACTION='WRITE', STATUS='REPLACE'
UNITS: N/A
TYPE: INTEGER
DIMENSION: Scalar
ATTRIBUTES: INTENT( IN ), OPTIONAL
No_Check: Set this optional argument to suppress the byte-order
check made on an existing file by NOT reading the file
header magic number. Default action is to check the
file. This argument is ignored if the FOR_OUTPUT
optional argument is set.
If == 0, existing file magic number is read and the
byte order is checked (DEFAULT)
== 1, magic number is *NOT* read from file and
checked for validity.
UNITS: N/A
TYPE: INTEGER
DIMENSION: Scalar
ATTRIBUTES: INTENT( IN ), OPTIONAL
Message_Log: Character string specifying a filename in which any
Messages will be logged. If not specified, or if an
error occurs opening the log file, the default action
is to output Messages to the screen.
UNITS: N/A
TYPE: CHARACTER(*)
DIMENSION: Scalar
ATTRIBUTES: INTENT( IN ), OPTIONAL
OUTPUT ARGUMENTS:
FileID: File unit number.
UNITS: N/A
TYPE: INTEGER
DIMENSION: Scalar
ATTRIBUTES: INTENT( OUT )
OPTIONAL OUTPUT ARGUMENTS:
None.
FUNCTION RESULT:
Error_Status: The return value is an integer defining the
error status. The error codes are defined in
the ERROR_HANDLER module. Values returned by
this function are:
SUCCESS == file open was successful
FAILURE == - error occurred during file open,
- error occurred during file check.
UNITS: N/A
TYPE: INTEGER
DIMENSION: Scalar
CALLS:
Check_Binary_File: Function to determine if the unformatted
Binary file is in the correct byte order.
File_Exists: Function to determine if a named file exists.
SOURCE: File_Utility module
Get_Lun: Function to return a free logical unit number
for file access.
SOURCE: File_Utility module
Display_Message: Subroutine to output Messages
SOURCE: Error_Handler module
SIDE EFFECTS:
None.
RESTRICTIONS:
File open ACCESS and FORM specifiers are set to 'SEQUENTIAL' and
'UNFORMATTED' respectively.
CREATION HISTORY:
Written by: Paul van Delst, CIMSS/SSEC 12-July-2000
paul.vandelst@ssec.wisc.edu
(See Binary_File_Utility.f90)