Show bytes as a hex dump, and find where two raw vectors differ

bin_hexdump() formats n bytes of x from the 0-based byte offset the way xxd does: each line is the offset of its first byte in hex, the bytes in hex in groups of two, and the bytes as ASCII, with . for anything not printable. Offsets are 0-based and absolute, so a dump from offset = 64 starts at 00000040.

Usage

bin_hexdump(x, offset = 0, n = NULL, width = 16L)

bin_diff(a, b, n = 10L)

Arguments

x, a, b

Raw vectors.

offset

The 0-based position of the first byte to show; at most length(x), or the call is a zubin_bounds_error.

n

For bin_hexdump(), the number of bytes to show, or NULL for the rest; for bin_diff(), the most differences to list.

width

Bytes per line, 1 to 256.

Value

bin_hexdump() returns a character vector of class zubin_hexdump, one line per element, which prints as the dump. bin_diff() returns a data frame with columns offset (double), a and b (raw), and attributes length_a and length_b.

Details

bin_diff() lists the first n positions, 0-based, at which a and b hold different bytes, comparing over the shorter length; the lengths themselves are attributes, so a prefix shows as no rows and two different lengths.

Both are presentation: they take any raw vector, and n past the end of x shows what there is.

Examples

x <- charToRaw("Structured binary data, one layout at a time.")
bin_hexdump(x)
#> 00000000: 5374 7275 6374 7572 6564 2062 696e 6172  Structured binar
#> 00000010: 7920 6461 7461 2c20 6f6e 6520 6c61 796f  y data, one layo
#> 00000020: 7574 2061 7420 6120 7469 6d65 2e         ut at a time.
bin_hexdump(x, offset = 16, n = 16, width = 8)
#> 00000010: 7920 6461 7461 2c20  y data, 
#> 00000018: 6f6e 6520 6c61 796f  one layo

y <- x
y[c(3, 20)] <- as.raw(0)
bin_diff(x, y)
#>   offset  a  b
#> 1      2 72 00
#> 2     19 61 00