ByteStream

Object represents stream of bytes

Instance attributes

eos: bool: Indicates, if current position is in the end of byte stream

pos: int: Current position in the byte stream

size: int: Size of byte stream in bytes

Instance methods

seek(position, origin=SeekOrigin::Begin): int

Change current position in byte stream.

Table 1. Parameters
position	Integer	Offset to seek to, relative to `origin`
origin	Integer	Optional. Reference position, one of the SeekOrigin constants. Defaults to `SeekOrigin::Begin`.

Return

Actual position if position change was successful or -1 if position change was not successful.

readByte(): int (32 bit): Read byte from byte stream and return it’s value. Returns 0 if current position is at the end of the stream.

readInt16B(): int (32 bit): Read big-endian 16-bit signed integer from byte stream and return it’s value.

readInt32B(): int (32 bit): Read big-endian 32-bit signed integer from byte stream and return it’s value.

readInt64B(): int (64 bit): Read big-endian 64-bit signed integer from byte stream and return it’s value.

readUInt16B(): int (32 bit): Read big-endian 16-bit unsigned integer from byte stream and return it’s value.

readUInt32B(): int (32 bit): Read big-endian 32-bit unsigned integer from byte stream and return it’s value.

readUInt64B(): int (64 bit): Read big-endian 64-bit unsigned integer from byte stream and return it’s value.

readFloatB(): floating-point number: Read 8 bytes from stream as big-endian floating-point number and return it’s value. Deprecated from v 5.1.2, readFloat64B should be used instead.

readFloat32B(): floating-point number (32 bit): Read 4 bytes from stream as big-endian floating-point number and return it’s value.

readFloat64B(): floating-point number (64 bit): Read 8 bytes from stream as big-endian floating-point number and return it’s value.

readInt16L(): int (32 bit): Read little-endian 16-bit signed integer from byte stream and return it’s value.

readInt32L(): int (32 bit): Read little-endian 32-bit signed integer from byte stream and return it’s value.

readInt64L(): int (64 bit): Read little-endian 64-bit signed integer from byte stream and return it’s value.

readUInt16L(): int (32 bit): Read little-endian 16-bit unsigned integer from byte stream and return it’s value.

readUInt32L(): int (32 bit): Read little-endian 32-bit unsigned integer from byte stream and return it’s value.

readUInt64L(): int (64 bit): Read little-endian 64-bit unsigned integer from byte stream and return it’s value.

readFloatL(): floating-point number: Read 8 bytes from stream as little-endian floating-point number and return it’s value. Deprecated from v 5.1.2, readFloat64L should be used instead.

readFloat32L(): floating-point number (32 bit): Read 4 bytes from stream as little-endian floating-point number and return it’s value.

readFloat64L(): floating-point number (64 bit): Read 8 bytes from stream as little-endian floating-point number and return it’s value.

readCString(codepage): String

Read C-string from stream and return it’s value. It’s expected that string in the stream is terminated by a null character.

Table 2. Parameters
codepage	String	Optional. Code page of the string in the stream, for example `UTF-8`, `ASCII`, `UCS-2` or `UCS-4`. System default code page is used if omitted.

Return

String value, or null if the stream contains no terminating null character or the string cannot be decoded.

readPString(codepage): String

Read length-prefixed string from stream and return it’s value. The string in the stream must be preceded by its length in bytes as a big-endian number: 2 bytes, or 4 bytes if the highest bit of the first byte is set (the format written by writePString()).

Table 3. Parameters
codepage	String	Optional. Code page of the string in the stream, for example `UTF-8`, `ASCII`, `UCS-2` or `UCS-4`. System default code page is used if omitted.

Return

String value, or null if the stream does not contain the whole string or the string cannot be decoded.

readString(length, codepage): String

Read string from stream and return it’s value.

Table 4. Parameters
length	Integer	Length of the string in bytes
codepage	String	Optional. Code page of the string in the stream, for example `UTF-8`, `ASCII`, `UCS-2` or `UCS-4`. System default code page is used if omitted.

Return

String value, or null if the stream has fewer than length bytes left or the string cannot be decoded.

writeByte(value): void: Write provided value as byte to the byte stream at current position.

writeInt16B(value): void: Write provided value to the byte stream as big-endian 16-bit integer .

writeInt32B(value): void: Write provided value to the byte stream as big-endian 32-bit integer.

writeInt64B(value): void: Write provided value to the byte stream as big-endian 64-bit integer.

writeFloatB(value): void: Write provided value to the byte stream as big-endian 64-bit float. Deprecated from v 5.1.2, writeFloat64B should be used instead. Value must be a floating-point number; passing an integer causes a runtime error.

writeFloat32B(value): void: Write provided value to the byte stream as big-endian 32-bit float. Value must be a floating-point number; passing an integer causes a runtime error.

writeFloat64B(value): void: Write provided value to the byte stream as big-endian 64-bit float. Value must be a floating-point number; passing an integer causes a runtime error.

writeInt16L(value): void: Write provided value to the byte stream as little-endian 16-bit integer.

writeInt32L(value): void: Write provided value to the byte stream as little-endian 32-bit integer.

writeInt64L(value): void: Write provided value to the byte stream as little-endian 64-bit integer.

writeFloatL(value): void: Write provided value to the byte stream as little-endian 64-bit float. Deprecated from v 5.1.2, writeFloat64L should be used instead. Value must be a floating-point number; passing an integer causes a runtime error.

writeFloat32L(value): void: Write provided value to the byte stream as little-endian 32-bit float. Value must be a floating-point number; passing an integer causes a runtime error.

writeFloat64L(value): void: Write provided value to the byte stream as little-endian 64-bit float. Value must be a floating-point number; passing an integer causes a runtime error.

writeCString(string, codepage): int

Write provided string to the byte stream as null-terminated string (C-string).

Table 5. Parameters
string	String	String to write
codepage	String	Optional. Code page to encode the string with, for example `UTF-8`, `ASCII`, `UCS-2` or `UCS-4`. System default code page is used if omitted.

Return

Number of bytes written.

writePString(string, codepage): int

Write provided string to the byte stream, preceded by its length in bytes (2-byte big-endian number, or 4 bytes with the highest bit set for long strings). Use readPString() to read it back.

Table 6. Parameters
string	String	String to write
codepage	String	Optional. Code page to encode the string with, for example `UTF-8`, `ASCII`, `UCS-2` or `UCS-4`. System default code page is used if omitted.

Return

Number of bytes written.

writeString(string, codepage): int

Write provided string to the byte stream.

Table 7. Parameters
string	String	String to write
codepage	String	Optional. Code page to encode the string with, for example `UTF-8`, `ASCII`, `UCS-2` or `UCS-4`. System default code page is used if omitted.

Return

Number of bytes written.

Constructors

ByteStream(): Creates new byte stream.

Return

ByteStream object.

bytestream = new ByteStream();
bytestream.writeString("xyz");
bytestream.seek(0);
while (!bytestream.eos) {
  b = bytestream.readByte();
  print(d2x(b,2) .. " "); // prints "78 79 7A"
}