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The CPXgetnetcallbackfunc accesses the
 user-written callback routine to be called each time a log message is issued
 during the optimization of a network problem. If the display log is turned
 off, the callback routine is still called.
This routine works in the same way as the routine
 CPXgetlpcallbackfunc. It enables the user
 to create a separate callback function to be called during the solution of
 a network problem. The prototype for the callback function is identical to
 that of CPXgetlpcallbackfunc. 
Callback description
 int callback (CPXCENVptr env,
               void       *cbdata,
               int        wherefrom,
               void       *cbhandle);
 This is the user-written callback routine.
Callback return value
A nonzero terminates the optimization.
Callback arguments
env
A pointer to the CPLEX environment that was passed into the associated optimization routine.
cbdata
A pointer passed from the optimization routine to the user-written
 callback function that identifies the problem being optimized. The only
 purpose for the cbdata pointer is to pass it to the routine
 CPXgetcallbackinfo.
wherefrom
An integer value indicating which optimization algorithm the user-written callback function was called from. Possible values and their meaning appear in the table.
| Value | Symbolic Constant | Meaning | 
3 | CPX_CALLBACK_NETWORK | From network simplex | 
cbhandle
Pointer to user private data, as passed to
 CPXsetlpcallbackfunc.
Parameters
env
A pointer to the CPLEX environment 
 as returned by CPXopenCPLEX.
callback
The address of the pointer to the current user-written callback function. If no callback function has been set, the pointer evaluates to NULL.
cbhandle_p
The address of a variable to hold the private pointer of the user.
Example
status = CPXgetnetcallbackfunc (env, mycallback, NULL);
See Also: