Machine encodings

This section describes the structure of the Encoding field in the message descriptor.

See MQMD - Message descriptor for a summary of the fields in the structure.

• The encoding used for binary integers
• The encoding used for packed-decimal integers
• The encoding used for floating-point numbers
• Reserved bits

Each subfield is identified by a bit mask that has 1-bits in the positions corresponding to the subfield, and 0-bits elsewhere. The bits are numbered such that bit 0 is the most significant bit, and bit 31 the least significant bit. The following masks are defined:

MQENC_INTEGER_MASK

Mask for binary-integer encoding.

This subfield occupies bit positions 28 through 31 within the Encoding field.

MQENC_DECIMAL_MASK

Mask for packed-decimal-integer encoding.

This subfield occupies bit positions 24 through 27 within the Encoding field.

MQENC_FLOAT_MASK

Mask for floating-point encoding.

This subfield occupies bit positions 20 through 23 within the Encoding field.

MQENC_RESERVED_MASK

Mask for reserved bits.

This subfield occupies bit positions 0 through 19 within the Encoding field.

• Binary-integer encoding
  
• Packed-decimal-integer encoding
  
• Floating-point encoding
  
• Constructing encodings
  
• Analyzing encodings
  The Encoding field contains subfields; because of this, applications that need to examine the integer, packed decimal, or float encoding must use one of the techniques described.
• Summary of machine architecture encodings
  

Parent topic: MQI applications reference