# Module Digest

    module Digest: sig  end

MD5 message digest.

This module provides functions to compute 128-bit ``digests'' of arbitrary-length strings or files. The digests are of cryptographic quality: it is very hard, given a digest, to forge a string having that digest. The algorithm used is MD5.

`type t = `string``
The type of digests: 16-character strings.

    val string : string -> t

Return the digest of the given string.

    val substring : string -> int -> int -> t

`Digest.substring s ofs len` returns the digest of the substring of `s` starting at character number `ofs` and containing `len` characters.

    val channel : Pervasives.in_channel -> int -> t

If `len` is nonnegative, `Digest.channel ic len` reads `len` characters from channel `ic` and returns their digest, or raises `End_of_file` if end-of-file is reached before `len` characters are read. If `len` is negative, `Digest.channel ic len` reads all characters from `ic` until end-of-file is reached and return their digest.

    val file : string -> t

Return the digest of the file whose name is given.

    val output : Pervasives.out_channel -> t -> unit

Write a digest on the given output channel.

    val input : Pervasives.in_channel -> t

Read a digest from the given input channel.

    val to_hex : t -> string

Return the printable hexadecimal representation of the given digest.