Documentation for MD5 interface.

doc/scsh-manual/miscprocs.tex

@@ -357,6 +357,53 @@ not necessary to explicitly open a syslog channel to do logging.
   specified form of calling \ex{syslog} logs to the specified channel.
 \end{desc}
 
+
+\section{MD5 interface}
+\label{sec:md5}
+
+Scsh provides a direct interface to the MD5 functions to compute the
+``fingerprint'' or ``message digest'' of a file or string. It uses the
+C library written by Colin Plum.
+
+\defun{md5-digest-for-string}{string}{md5-digest}
+\begin{desc}
+  Calculates the MD5 digest for the given string.
+\end{desc}
+\defun{md5-digest-for-port}{port [buffer-size]}{md5-digest}
+\begin{desc}
+  Reads the contents of the port and calculates the MD5 digest for it.
+\end{desc}
+
+\defun{md5-digest?}{thing}{boolean}
+\begin{desc}
+  The type predicate for MD5 digests: \ex{md5-digest?} returns true if
+  and only if \var{thing} is a MD5 digest.
+\end{desc}
+\defun{md5-digest->number}{md5-digest}{number}
+\begin{desc}
+  Returns the number corresponding to the MD5 digest.
+\end{desc}
+\defun{number->md5-digest}{number}{md5-digest}
+\begin{desc}
+  Creates a MD5 digest from a number.
+\end{desc}
+
+\defun{make-md5-context}{}{md5-context}
+\defunx{md5-context?}{thing}{boolean}
+\defunx{update-md5-context!}{md5-context string}\undefined
+\defunx{md5-context->md5-digest}{md5-context}{md5-digest}
+\begin{desc}
+  These procedures provide a low-level interface to the library. A
+  \var{md5-context} stores the state of a MD5 computation, it is
+  created by \ex{make-md5-context}, its type predicate is
+  \ex{md5-context?}. The procedure \ex{update-md5-context!} extends
+  the \var{md5-context} by the given string. Finally,
+  \ex{md5-context->md5-digest} returns the \var{md5-digest} for the
+  \var{md5-context}. With these procedures it is possible to
+  incrementally add strings to a \var{md5-context} before computing
+  the digest.
+\end{desc}
+
 %%% Local Variables: 
 %%% mode: latex
 %%% TeX-master: "man"