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     ENCODE(2)                                               ENCODE(2)

              delim $$

     NAME
          dec64, enc64, dec32, enc32, dec16, enc16, encodefmt -
          encoding byte arrays as strings

     SYNOPSIS
          #include <u.h>
          #include <libc.h>

          int  dec64(uchar *out, int lim, char *in, int n)

          int  enc64(char *out, int lim, uchar *in, int n)

          int  dec32(uchar *out, int lim, char *in, int n)

          int  enc32(char *out, int lim, uchar *in, int n)

          int  dec16(uchar *out, int lim, char *in, int n)

          int  enc16(char *out, int lim, uchar *in, int n)

          int  encodefmt(Fmt*)

     DESCRIPTION
          Enc16, enc32 and enc64 create null terminated strings.  They
          return the size of the encoded string (without the null) or
          -1 if the encoding fails.  The encoding fails if lim, the
          length of the output buffer, is too small.  They require $2
          n + 1$, ${ 8 n + 4 } over 5 + 1$ and $4 { { n + 2 } over 3 }
          + 1$ bytes, respectively.

          Dec16, dec32 and dec64 return the number of bytes decoded or
          -1 if the decoding fails.  The decoding fails if the output
          buffer is not large enough or, for base 32, if the input
          buffer length is not a multiple of 8.

          Encodefmt can be used with fmtinstall(2) and print(2) to
          print encoded representations of byte arrays.  The verbs are

          H  base 16 (i.e. hexadecimal). The default encoding is in
             upper case.  The l flag forces lower case.

          <  base 32

          [  base 64 (same as MIME)

          The length of the array is specified as f2. For example, to
          display a 15 byte array as hex:

               char x[15];

     ENCODE(2)                                               ENCODE(2)

               fmtinstall('H', encodefmt);
               print("%.*H\n", sizeof x, x);

     SOURCE
          /sys/src/libc/port/u[136][246].c