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diff --git a/Doc/lib/libbinascii.tex b/Doc/lib/libbinascii.tex deleted file mode 100644 index 84d29c6..0000000 --- a/Doc/lib/libbinascii.tex +++ /dev/null @@ -1,147 +0,0 @@ -\section{\module{binascii} --- - Convert between binary and \ASCII} - -\declaremodule{builtin}{binascii} -\modulesynopsis{Tools for converting between binary and various - \ASCII-encoded binary representations.} - - -The \module{binascii} module contains a number of methods to convert -between binary and various \ASCII-encoded binary -representations. Normally, you will not use these functions directly -but use wrapper modules like \refmodule{uu}\refstmodindex{uu}, -\refmodule{base64}\refstmodindex{base64}, or -\refmodule{binhex}\refstmodindex{binhex} instead. The \module{binascii} module -contains low-level functions written in C for greater speed -that are used by the higher-level modules. - -The \module{binascii} module defines the following functions: - -\begin{funcdesc}{a2b_uu}{string} -Convert a single line of uuencoded data back to binary and return the -binary data. Lines normally contain 45 (binary) bytes, except for the -last line. Line data may be followed by whitespace. -\end{funcdesc} - -\begin{funcdesc}{b2a_uu}{data} -Convert binary data to a line of \ASCII{} characters, the return value -is the converted line, including a newline char. The length of -\var{data} should be at most 45. -\end{funcdesc} - -\begin{funcdesc}{a2b_base64}{string} -Convert a block of base64 data back to binary and return the -binary data. More than one line may be passed at a time. -\end{funcdesc} - -\begin{funcdesc}{b2a_base64}{data} -Convert binary data to a line of \ASCII{} characters in base64 coding. -The return value is the converted line, including a newline char. -The length of \var{data} should be at most 57 to adhere to the base64 -standard. -\end{funcdesc} - -\begin{funcdesc}{a2b_qp}{string\optional{, header}} -Convert a block of quoted-printable data back to binary and return the -binary data. More than one line may be passed at a time. -If the optional argument \var{header} is present and true, underscores -will be decoded as spaces. -\end{funcdesc} - -\begin{funcdesc}{b2a_qp}{data\optional{, quotetabs, istext, header}} -Convert binary data to a line(s) of \ASCII{} characters in -quoted-printable encoding. The return value is the converted line(s). -If the optional argument \var{quotetabs} is present and true, all tabs -and spaces will be encoded. -If the optional argument \var{istext} is present and true, -newlines are not encoded but trailing whitespace will be encoded. -If the optional argument \var{header} is -present and true, spaces will be encoded as underscores per RFC1522. -If the optional argument \var{header} is present and false, newline -characters will be encoded as well; otherwise linefeed conversion might -corrupt the binary data stream. -\end{funcdesc} - -\begin{funcdesc}{a2b_hqx}{string} -Convert binhex4 formatted \ASCII{} data to binary, without doing -RLE-decompression. The string should contain a complete number of -binary bytes, or (in case of the last portion of the binhex4 data) -have the remaining bits zero. -\end{funcdesc} - -\begin{funcdesc}{rledecode_hqx}{data} -Perform RLE-decompression on the data, as per the binhex4 -standard. The algorithm uses \code{0x90} after a byte as a repeat -indicator, followed by a count. A count of \code{0} specifies a byte -value of \code{0x90}. The routine returns the decompressed data, -unless data input data ends in an orphaned repeat indicator, in which -case the \exception{Incomplete} exception is raised. -\end{funcdesc} - -\begin{funcdesc}{rlecode_hqx}{data} -Perform binhex4 style RLE-compression on \var{data} and return the -result. -\end{funcdesc} - -\begin{funcdesc}{b2a_hqx}{data} -Perform hexbin4 binary-to-\ASCII{} translation and return the -resulting string. The argument should already be RLE-coded, and have a -length divisible by 3 (except possibly the last fragment). -\end{funcdesc} - -\begin{funcdesc}{crc_hqx}{data, crc} -Compute the binhex4 crc value of \var{data}, starting with an initial -\var{crc} and returning the result. -\end{funcdesc} - -\begin{funcdesc}{crc32}{data\optional{, crc}} -Compute CRC-32, the 32-bit checksum of data, starting with an initial -crc. This is consistent with the ZIP file checksum. Since the -algorithm is designed for use as a checksum algorithm, it is not -suitable for use as a general hash algorithm. Use as follows: -\begin{verbatim} - print binascii.crc32("hello world") - # Or, in two pieces: - crc = binascii.crc32("hello") - crc = binascii.crc32(" world", crc) - print crc -\end{verbatim} -\end{funcdesc} - -\begin{funcdesc}{b2a_hex}{data} -\funcline{hexlify}{data} -Return the hexadecimal representation of the binary \var{data}. Every -byte of \var{data} is converted into the corresponding 2-digit hex -representation. The resulting string is therefore twice as long as -the length of \var{data}. -\end{funcdesc} - -\begin{funcdesc}{a2b_hex}{hexstr} -\funcline{unhexlify}{hexstr} -Return the binary data represented by the hexadecimal string -\var{hexstr}. This function is the inverse of \function{b2a_hex()}. -\var{hexstr} must contain an even number of hexadecimal digits (which -can be upper or lower case), otherwise a \exception{TypeError} is -raised. -\end{funcdesc} - -\begin{excdesc}{Error} -Exception raised on errors. These are usually programming errors. -\end{excdesc} - -\begin{excdesc}{Incomplete} -Exception raised on incomplete data. These are usually not programming -errors, but may be handled by reading a little more data and trying -again. -\end{excdesc} - - -\begin{seealso} - \seemodule{base64}{Support for base64 encoding used in MIME email messages.} - - \seemodule{binhex}{Support for the binhex format used on the Macintosh.} - - \seemodule{uu}{Support for UU encoding used on \UNIX.} - - \seemodule{quopri}{Support for quoted-printable encoding used in MIME email messages. } -\end{seealso} |