@remy/unpack

unpack (and pack)

JavaScript module for unpacking and packing based loosely around the Perl packing syntax.

Working demo can be found at unpack.isthe.link.

Lookup table for unpacking:

• a A string with arbitrary binary data, will be null padded.
• A text (ASCII) string, will be space padded.
• b A bit string (ascending bit order inside each byte).
• c A signed char (8-bit) value.
• C An unsigned char (octet) value.
• s A signed short (16-bit) value.
• S An unsigned short value.
• i A signed integer (32-bit) value.
• I A unsigned integer value.
• l A signed long (64-bit) value.
• L An unsigned long value.
• n An unsigned short (16-bit) in "network" (big-endian) order.
• N An unsigned long (32-bit) in "network" (big-endian) order.
• f A single-precision float in native format.
• d A double-precision float in native format.
• x A null byte (a.k.a ASCII NUL, "\000", chr(0))

Each type can also include a number, such as A5 will unpack to a 5 byte ascii string.

Unless otherwise stated, endianness can be set to little by using <, such as: <I I L unpacks using little endian 2 32bit unsigned ints and 1 64 bit long.