AMIGA - DOS_#?
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   NAME

      dos_checkdevice() - Allows to check for DOS entry on
                          the list.



   SYNOPSIS

      dol = dos_checkdevice(name, type);

      struct DosList *dos_checkdevice(UBYTE *, LONG);



   FUNCTION

      This func. is useful when there is a need to query
      the device after it was created in a standalone proc.



   INPUTS

      name - Standard DOS device name lower or upper case,
             with or without the colon(':').

      type - Type of entry(DLT_DEVICE, DLT_VOLUME, ...).
             Ranges can be formed using upper 16 bits:
             'type = (DLT_NONBINDING << 16) | DLT_DEVICE;'
             where the range starts at DLT_DEVICE and ends
             at DLT_NONBINDING.



   RETURNS

      Returns DosList pointer or NULL if the device was not
      found.



   BASES

      SysBase, DOSBase



   NOTES

      You should really brace this function with 'Forbid()'
      / 'Permit()' pair! Functions such as 'LockDosList()'
      / 'UnLockDosList()' can also be used, but only in a
      process!

      It is best to combine this function in a delay sliced
      and time framed loop.

      This func. can be called safely from under the task!



   SEE ALSO

      dos_makedevice(), dos_killdevice()



   EXAMPLE

      ...

      #define ONESECOND   50
      #define LOOPDELAY    5
      #define TIMEOUT      \
              (ONESECOND / \
               LOOPDELAY)

      /*
       * Argument 'timeout' expresses values in seconds or
       * will trigger one time check if 0 is to be passed.
      */
      struct DosList *checkdev(UBYTE *name, LONG timeout)
      {
        struct DosList *dol;


        timeout = ((timeout > 0) ? 
                                (timeout * TIMEOUT) : 1);

        Forbid();

        while (((dol =
           dos_checkdevice(name, DLT_DEVICE)) == NULL) &&
                                             (--timeout))
        {
          /*
           * This will break forbidden state temporarily!
          */
          Delay(LOOPDELAY);
        }

        Permit();

        return dol;
      }



   BUGS

      None known.



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