GXBF class¶

class geosoft.gx.GXBF¶

The BF class is used to access (or create) Binary files and remove
(or destroy) files from use. You can also perform a variety of
additional tasks, such as positioning within files, reading from
files and writing to files.

ch_size((int)arg1) → None:¶

Changes the size of a file

Parameters:	arg1 (int) – new length in bytes
Returns:	Nothing
Return type:	None

New in version 5.0.0.

copy((GXBF)arg1) → None:¶

Copy entire contents of a source BF to a destination BF

Parameters:	arg1 (`geosoft.gx.GXBF`) – Destination BF
Returns:	Nothing
Return type:	None

New in version 5.0.0.

crc((int)arg1, (int)arg2) → int:¶

Compute CRC of a file.

Parameters:	arg1 (int) – number of bytes to CRC arg2 (int) – CRC start (use CRC_INIT_VALUE constant for new)
Returns:	CRC Value
Return type:	int

New in version 5.0.0.

static create((GXContext)ctx, (str)arg1, (int)arg2) → GXBF:¶

Create BF object.

Parameters:	ctx (`geosoft.gx.GXContext`) – The GX execution context arg1 (str) – file name to open (“” is a temporary file) arg2 (int) – BF_OPEN_MODE constants
Returns:	BF Object
Return type:	`geosoft.gx.GXBF`

New in version 5.0.0.

Note:

Run-time specific directory paths may be added the the front of file names
as follows:

      <geosoft>      the main Geosoft installation directory
      <geosoft2>     the secondary Geosoft installation directory
      <geotemp>      the Geosoft temporary file directory
      <windows>      the operating system Windows directory
      <system>       the operating system system directory
      <other>        other environment variables

For example "<geosoft>/user/csv/datum.csv"

static create_sbf((GXContext)ctx, (GXSBF)arg1, (str)arg2, (int)arg3) → GXBF:¶

Create BF object inside an SBF.

Parameters:	ctx (`geosoft.gx.GXContext`) – The GX execution context arg1 (`geosoft.gx.GXSBF`) – Storage arg2 (str) – file name to open (“” is a temporary file) arg3 (int) – BF_OPEN_MODE constants
Returns:	BF Object
Return type:	`geosoft.gx.GXBF`

New in version 5.0.0.

Note:

see sbf.gxh

eof() → int:¶

Returns 1 if at the end of the file

Returns:	1 if at the end of the file, 0 if not at the end of the file
Return type:	int

New in version 5.0.0.

is_null() → bool¶

Check if the instance of geosoft.gx.GXBF is null (undefined)

Returns:	True if this is a null instance of `geosoft.gx.GXBF`, False otherwise.
Return type:	bool`

static null() → GXBF¶

A null (undefined) instance of geosoft.gx.GXBF

Returns:	A null `geosoft.gx.GXBF`
Return type:	`geosoft.gx.GXBF`

query_write() → int:¶

Check if you can write to the BF.

Returns:	0 - No 1 - Yes
Return type:	int

New in version 5.1.1.

read_binary_string((int)arg1, (int)arg2, (str_ref)arg3) → None:¶

Reads string data from current position in BF

Parameters:	arg1 (int) – Number of bytes to read arg2 (int) – BF_ENCODE constants arg3 (`geosoft.gx.str_ref`) – data
Returns:	Nothing
Return type:	None

New in version 6.3.0.

read_double((int)arg1, (float_ref)arg2) → None:¶

Reads real data from current position in BF

Parameters:	arg1 (int) – GS_TYPES constants and BF_BYTEORDER constants arg2 (`geosoft.gx.float_ref`) – data
Returns:	Nothing
Return type:	None

New in version 5.0.0.

Note:

If the data source may be in byte order different from that
required by the reader, you can add the source byte-order
to the BF elelment type.  The byte order will be swapped
if required.  For example, to write out a real number 3.5
with Most-Significant_Byte first (Mortorola) convention:

geosoft.gx.GXBF.write_double()(hBF,BF_BYTEORDER_MSB+GS_REAL,3.5).

If a byte order is not specified, the source is assumed to be
in the native byte order of the reading/writing computer.

read_int((int)arg1, (int_ref)arg2) → None:¶

Reads int data from current position in BF

Parameters:	arg1 (int) – GS_TYPES constants and BF_BYTEORDER constants arg2 (`geosoft.gx.int_ref`) – data
Returns:	Nothing
Return type:	None

New in version 5.0.0.

Note:

If the data source may be in byte order different from that
required by the reader, you can add the source byte-order
to the BF elelment type.  The byte order will be swapped
if required.  For example, to write out a real number 3.5
with Most-Significant_Byte first (Mortorola) convention:

geosoft.gx.GXBF.write_double()(hBF,BF_BYTEORDER_MSB+GS_REAL,3.5).

If a byte order is not specified, the source is assumed to be
in the native byte order of the reading/writing computer.

read_vv((int)arg1, (GXVV)arg2) → None:¶

Read data to a VV from current position in BF

Parameters:	arg1 (int) – GS_TYPES constants and BF_BYTEORDER constants arg2 (`geosoft.gx.GXVV`) – VV data to read, VV length is read
Returns:	Nothing
Return type:	None

New in version 5.0.0.

Note:

If the data source may be in byte order different from that
required by the reader, you can add the source byte-order
to the BF elelment type.  The byte order will be swapped
if required.  For example, to write out a real number 3.5
with Most-Significant_Byte first (Mortorola) convention:

geosoft.gx.GXBF.write_double()(hBF,BF_BYTEORDER_MSB+GS_REAL,3.5).

If a byte order is not specified, the source is assumed to be
in the native byte order of the reading/writing computer.

seek((int)arg1, (int)arg2) → None:¶

Moves file position

Parameters:	arg1 (int) – number of bytes from reference point arg2 (int) – BF_SEEK constants
Returns:	Nothing
Return type:	None

New in version 5.0.0.

Note:

Terminates if attempt to move past the end of
a read-only file.

set_destroy_status((int)arg1) → None:¶

Set the flag to delete the file on close

Parameters:	arg1 (int) – BF_CLOSE constants
Returns:	Nothing
Return type:	None

New in version 6.0.0.

size() → int:¶

Returns the file length

Returns:	File size in bytes.
Return type:	int

New in version 5.0.0.

tell() → int:¶

Returns current position of file pointer in bytes

Returns:	Current file pointer location
Return type:	int

New in version 5.0.0.

write_binary_string((int)arg1, (str)arg2) → None:¶

Write a binary string to a BF

Parameters:	arg1 (int) – BF_ENCODE constants arg2 (str) – string to write out
Returns:	Nothing
Return type:	None

New in version 6.3.0.

write_data_null() → None:¶

Writes a null byte (0) to BF

Returns:	Nothing
Return type:	None

New in version 5.0.0.

write_double((int)arg1, (float)arg2) → None:¶

Writes real to the BF

Parameters:	arg1 (int) – GS_TYPES constants and BF_BYTEORDER constants arg2 (float) – data
Returns:	Nothing
Return type:	None

New in version 5.0.0.

Note:

See comments on byte order for the Read.. functions if you
want to enforce a certain byte order.

If a byte order is not specified, the data is written
in the native byte order of the writing computer.

write_int((int)arg1, (int)arg2) → None:¶

Writes int to the BF

Parameters:	arg1 (int) – GS_TYPES constants and BF_BYTEORDER constants arg2 (int) – data
Returns:	Nothing
Return type:	None

New in version 5.0.0.

Note:

See comments on byte order for the Read.. functions if you
want to enforce a certain byte order.

If a byte order is not specified, the data is written
in the native byte order of the writing computer.

write_vv((int)arg1, (GXVV)arg2) → None:¶

Writes VV to the BF

Parameters:	arg1 (int) – GS_TYPES constants and BF_BYTEORDER constants arg2 (`geosoft.gx.GXVV`) – data
Returns:	Nothing
Return type:	None

New in version 5.0.0.

Note:

See comments on byte order for the Read.. functions if you
want to enforce a certain byte order.

If a byte order is not specified, the data is written
in the native byte order of the writing computer.

BF_BYTEORDER constants¶

Byte order for read/write

gx.BF_BYTEORDER_LSB = 256¶

Least significant byte first (Intel, Windows)

gx.BF_BYTEORDER_MSB = 512¶

Most significant byte first (Mororola, Sun)

BF_CLOSE constants¶

Close Flags

gx.BF_KEEP = 0¶

gx.BF_DELETE = 1¶

BF_ENCODE constants¶

The way a string is encoded

gx.BF_ENCODE_ANSI = 0¶

String is stored as ANSI code page

gx.BF_ENCODE_UTF8 = 1¶

String is stored as UTF8

BF_OPEN_MODE constants¶

Open Status

gx.BF_READ = 0¶

Read only

gx.BF_READWRITE_NEW = 1¶

erases existing file

gx.BF_READWRITE_OLD = 2¶

file must pre-exist

gx.BF_READWRITE_APP = 4¶

open and append onto pre-existing file (cannot be read from)

BF_SEEK constants¶

Seek Location

gx.BF_SEEK_START = 0¶

gx.BF_SEEK_CURRENT = 1¶

gx.BF_SEEK_EOF = 2¶

GXBF class¶

BF_BYTEORDER constants¶

BF_CLOSE constants¶

BF_ENCODE constants¶

BF_OPEN_MODE constants¶

BF_SEEK constants¶

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