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SMG examples?

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The Question is:

 
HELP!  - > I can't get smg$read_string() to work from C.  Every time
I call it, my program crashes with an access violation.  I have carefully
examined each argument against what the manual specifies and they each appear
correct.  The smg$ manual, however, shows no examples in C (isn't that sorta
odd?).  Could you show me how to use this system service from C?  Maybe you
could point me to some smg$ programming examples in C.
 
Thanks a bunch,
John E. Frank
 
 


The Answer is :

 
  Without seeing the failing source code, it is difficult to say exactly
  what has happened.
 
  The ACCVIO message contains information on exactly what the cause of the
  access violation was, including the failing program counter address, the
  virtual address that the access attempt failed on, and whether or not the
  request was a read or a write.
 
  Among the more common causes of program failures in C programs written by
  programmers new to C on OpenVMS involve string descriptors -- either the
  incorrect specification of a string descriptor correctly, or failure to
  (correctly) pass the string descriptor by reference.  (Those programmers
  new to C on OpenVMS, and thus new to string descriptors, should start by
  practicing various calls to the lib$put_output library call.)
 
  There are obviously many other potential causes of an access violation.
 
  There are far too many library routines and far too may system services
  to make examples of each routine in a particular language available.
 
  See the OpenVMS Frequently Asked Questions (FAQ) for pointers to example
  source code areas, such as the Freeware CD-ROM.  On the DISK$FREEWAREV30
  distribution, look under [EMON021-3] and [GOPHER] for example C source
  code that calls SMG.  There are other examples of calls to SMG available
  from a variety of sources, including (if you have a software support
  contract) DSNlink.
 

answer written or last revised on ( 8-JUL-1998 )

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