Procedure

   SpiceBoolean gfbail_c () 

Abstract

 
   Indicate whether an interrupt signal (SIGINT) has been received. 
 

Required_Reading

 
   GF
 

Keywords

 
   GEOMETRY
   SEARCH 
   UTILITY 
 

Brief_I/O

 
   The function returns SPICETRUE if an interrupt signal has
   been received by the GF handler.
 

Detailed_Input

 
   None 
 

Detailed_Output

 
   The function returns SPICETRUE if an interrupt signal has been
   received by the GF handler gfinth_c since the first setting of the
   handler or the last call to gfclrh_c, whichever is most recent.
   Otherwise the function returns SPICEFALSE.
 

Parameters

 
   None. 
 

Exceptions

 
   Error free.
 

Files

 
   None. 
 

Particulars

 
   This routine returns the interrupt signal handler status maintained
   by the GF subsystem. 

   User applications that use default GF interrupt handling should call
   this routine after each call to a GF API that can process an
   interrupt signal. In general, if this routine indicates that an
   interrupt signal was received, any GF processing that was interrupted
   should be presumed to have invalid results.
  

Examples

 
   1) The code fragment below is from an example program in
      the header of gfocce_c. The code includes a search,
      a call to gfbail_c, which is made to determine whether
      an interrupt signal was received, and a call to 
      gfclrh_c to clear the interrupt signal status.

            ...

            /.
            Turn on interrupt handling and progress reporting.
            ./
            bail = SPICETRUE;
            rpt  = SPICETRUE;

            /.
            Perform the search.
            ./
            gfocce_c ( "ANY",                            
                       "MOON",     "ellipsoid",  "IAU_MOON", 
                       "SUN",      "ellipsoid",  "IAU_SUN",  
                       "LT",       "EARTH",      CNVTOL,    
                       gfstep_c,   gfrefn_c,     rpt,       
                       gfrepi_c,   gfrepu_c,     gfrepf_c, 
                       bail,       gfbail_c,     &cnfine,   
                       &result                              );


            if ( gfbail_c() ) 
            {
               /.
               Clear the CSPICE interrupt indication. This is
               an essential step for programs that continue
               running after an interrupt; gfbail_c will
               continue to return SPICETRUE until this step
               has been performed.
               ./
               gfclrh_c();


               /.
               We've trapped an interrupt signal. In a realistic
               application, the program would continue operation
               from this point. In this simple example, we simply
               display a message and quit.
               ./
               printf ( "\nSearch was interrupted.\n\nThis message "
                        "was written after an interrupt signal\n"
                        "was trapped. By default, the program "
                        "would have terminated \nbefore this message "
                        "could be written.\n\n"                       );
            }
            else
            

            ...

Restrictions

 
   This routine has no visible effect on operation of user applications
   unless GF interrupt handling is enabled and this routine is used as
   the interrupt signal receipt indicator.
 

Literature_References

 
   None. 
 

Author_and_Institution

 
   N.J. Bachman   (JPL) 
   L.S. Elson     (JPL) 
 

Version

 
   -CSPICE Version 1.0.0, 05-FEB-2009 (NJB) (LSE)

Index_Entries

 
   GF interrupt signal receipt indicator
 

Link to routine gfbail_c source file gfbail_c.c