From: Jan Vorbrueggen <jan@vesta.neuroinformatik.ruhr-uni-bochum.de>
Date: Fri, 28 May 93 09:01:51 +0200

The new version of the iserver file filec.c-new does the following:

- converts \ in filenames to /
- squeeze \r out of text files on read

These changes allow us transparently share files with our PCs
(where the C run time library does the \r-squeezing) and 
transputer applications which have directory paths coded into
them.

The changes to filec.c are as follows:

- In SpOpen, the following is inserted; this converts
  DOS-style directory delimiters to Unix-style:

/* JV 17.8.1992 */
#ifdef SUN
   {int i;
   for (i = 0; i < strlen(Name); i++) 
      {
      if (*(Name+i) == '\\') 
         {
         *(Name+i) = '/';
         }
      }
   }
#endif

- I've defined an additional ifdef-flag called DOS_FILES.
  With this defined, three pieces of code are included:

1. In the declarations at the beginning, I define a flag bit
   which happens to be unused in the flag word of the file
   descriptor - at least on SunOs. This admittedly is a kludge,
   but saves a lot of work - and it _does_ work.

#ifdef DOS_FILES
#define TEXT_FLAG 010000
#endif
 
2. In SpOpen, if the transputer application says it's opening
   a text file for reading, this flag is set in the file descriptor:

#ifdef DOS_FILES
   if (Type == 2) Fd->_flag |= TEXT_FLAG;
#endif

3. In SpRead, if the flag is set for the file being read from,
   the block read is scanned for "\r", which are squeezed out and
   the number of bytes read are adjusted accordingly. As the block
   can only become smaller, this can be done in place:

#ifdef DOS_FILES
   if (Fd->_flag & TEXT_FLAG)
       {
       int i, j, incount;
       j = 0;
       incount = Read;
       for (i = 0; i < incount; i++)
           {
           if (DataBuffer[i] == '\r')
               {
               --Read;
               }
           else
               {
               DataBuffer[j] = DataBuffer[i];
               j++;
               }
           }
       }
#endif

I've used this iserver for almost a year now, regularly editing
files from both PC and Sun and compiling, linking etc. on both
without trouble, using the occam and C toolset. The toolset seems
to only use the block-mode SpRead and not the record-mode SpGets,
so that's all I touched.

Jan