following up a message from Pete Zieger to Mike Ruskai:

 MR> Anyone have the algorithm for uuen/decoding files?  I'd like to 
 MR> write en/decoders in REXX.

Here are the two uu programs from snippets:

uudecode.c

/*
** by: John Lots
** patched up for BC++ 3.1 by Alan Eldridge 10/12/92
**     (UUCP: alane{at}wozzle.linet.org, FIDO: 1:272/38.473)
*/

#include        
#include        
#define         DEC(c)  (char)(((c)-' ')&077)

int main()
{
      int     n;
      char    buf[128],a,b,c,d;

      scanf("begin %o ", &n);
      gets(buf);                              /* filename */
      if (!freopen(buf, "wb", stdout))         /* oops.. */
      {
            perror(buf);
            exit(1);
      }
      while ((n=getchar())!=EOF&&((n=DEC(n))!=0))
      {
            while (n>0)
            {
                  a=DEC(getchar());
                  b=DEC(getchar());
                  c=DEC(getchar());
                  d=DEC(getchar());
                  if (n-->0)
                        putchar((a>4));
                  if (n-->0)
                        putchar((b>2));
                  if (n-->0)
                        putchar((c<<6)|d);
            }
            n=getchar();                    /* skip \n */
      }
      return 0;
}


uuencode.c

/* uuencode.c */

/*
uudecode and uuencode are easily implemented under MSDOS as well.  Here are
the sources for Microsoft C v3.0, but if you have another kind of C
compiler, there should be perhaps only 1 change -- the output file of
uudecode and the input file of uuencode must be in binary format. (ie. 
binary files, like .EXE files may have byte patterns that are the same as
^Z, which signals end-of-file in non-binary (text) mode).

    Don Kneller
UUCP:   ...ucbvax!ucsfcgl!kneller
ARPA:   kneller{at}ucsf-cgl.ARPA
BITNET: kneller{at}ucsfcgl.BITNET

   patched up for BC++ 3.1 by Alan Eldridge 10/12/92
       (UUCP: alane{at}wozzle.linet.org, FIDO: 1:272/38.473)

*/

#ifndef lint
#ifndef MSDOS
static char sccsid[] = "{at}(#)uuencode.c  5.1 (Berkeley) 7/2/83"; #endif
#endif

/*
 * uuencode [input] output
 *
 * Encode a file so it can be mailed to a remote system.
 */

#include 
#include 
#include 
#include 

/* ENC is the basic 1 character encoding function to make a char printing */

#define ENC(c) (((c) & 077) + ' ')

void encode(FILE *in, FILE *out);
void outdec(char *p, FILE *f);
int fr(FILE *fd, char *buf, int cnt);

main(int argc, char *argv[])
{
      FILE *in;
      struct stat sbuf;
      int mode;

      /* optional 1st argument */

      if (argc > 2)
      {
#ifdef MSDOS
            /* Use binary mode */
            if ((in = fopen(argv[1], "rb")) == NULL)
            {
#else
            if ((in = fopen(argv[1], "r")) == NULL)
            {
#endif
                  perror(argv[1]);
                  exit(1);
            }
            argv++; argc--;
      }
      else  in = stdin;

      if (argc != 2)
      {
            printf("Usage: uuencode [infile] remotefile\n");
            exit(2);
      }

      /* figure out the input file mode */

      fstat(fileno(in), &sbuf);
      mode = sbuf.st_mode & 0777;
      printf("begin %o %s\n", mode, argv[1]);

      encode(in, stdout);

      printf("end\n");
      return 0;
}

/*
 * copy from in to out, encoding as you go along.
 */

void encode(FILE *in, FILE *out)
{
      char buf[80];
      int i, n;

      for (;;)
      {
            /* 1 (up to) 45 character line */

            n = fr(in, buf, 45);
            putc(ENC(n), out);

            for (i = 0; i < n; i += 3)
                  outdec(&buf[i], out);

            putc('\n', out);
            if (n <= 0)
                  break;
      }
}

/*
 * output one group of 3 bytes, pointed at by p, on file f.
 */

void outdec(char *p, FILE *f)
{
      int c1, c2, c3, c4;

      c1 = *p >> 2;
      c2 = ((p[0] > 4) & 017);
      c3 = ((p[1] > 6) & 03);
      c4 = p[2] & 077;
      putc(ENC(c1), f);
      putc(ENC(c2), f);
      putc(ENC(c3), f);
      putc(ENC(c4), f);
}

/* fr: like read but stdio */

int fr(FILE *fd, char *buf, int cnt)
{
      int c, i;

      for (i = 0; i < cnt; i++)
      {
            c = getc(fd);
            if (c == EOF)
                  return(i);
            buf[i] = (char)c;
      }
      return (cnt);
}


You should be able to figure out how to transliterate this into rexx.

loSmaH cha'

--- timEd-B9