petsc-master 2020-10-23
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PetscError

Routine that is called when an error has been detected, usually called through the macro SETERRQ(PETSC_COMM_SELF,).

Synopsis

#include "petscsys.h" 
PetscErrorCode PetscError(MPI_Comm comm,int line,const char *func,const char *file,PetscErrorCode n,PetscErrorType p,const char *mess,...)
Collective on comm

Input Parameters

comm - communicator over which error occurred. ALL ranks of this communicator MUST call this routine
line - the line number of the error (indicated by __LINE__)
func - the function name in which the error was detected
file - the file in which the error was detected (indicated by __FILE__)
n - the generic error number
p - PETSC_ERROR_INITIAL indicates the error was initially detected, PETSC_ERROR_REPEAT indicates this is a traceback from a previously detected error
mess - formatted message string - aka printf

Options Database

-error_output_stdout - output the error messages to stdout instead of the default stderr
-error_output_none - do not output the error messages

Notes

PETSc error handling is done with error return codes. A non-zero return indicates an error was detected. Errors are generally not something that the code can recover from. Note that numerical errors (potential divide by zero, for example) are not managed by the error return codes; they are managed via, for example, KSPGetConvergedReason() that indicates if the solve was successful or not. The option -ksp_error_if_not_converged, for example, turns numerical failures into hard errors managed via PetscError().

PETSc provides a rich supply of error handlers, see the list below, and users can also provide their own error handlers.

Most users need not directly use this routine and the error handlers, but can instead use the simplified interface SETERRQ, which has the calling sequence

    SETERRQ(comm,n,mess)

Fortran Note

This routine is used differently from Fortran
   PetscError(MPI_Comm comm,PetscErrorCode n,PetscErrorType p,char *message)

Set the error handler with PetscPushErrorHandler().

Developer Note: Since this is called after an error condition it should not be calling any error handlers (currently it ignores any error codes) BUT this routine does call regular PETSc functions that may call error handlers, this is problematic and could be fixed by never calling other PETSc routines but this annoying.

See Also

PetscErrorCode, PetscPushErrorHandler(), PetscPopErrorHandler(), PetscTraceBackErrorHandler(), PetscAbortErrorHandler(), PetscMPIAbortErrorHandler(),
PetscReturnErrorHandler(), PetscAttachDebuggerErrorHandler(), PetscEmacsClientErrorHandler(), SETERRQ(), CHKERRQ(), CHKMEMQ, SETERRQ1(), SETERRQ2(), PetscErrorMessage(), PETSCABORT()

Level

intermediate

Location

src/sys/error/err.c

Examples

src/vec/vec/tutorials/ex21.c.html

Index of all Sys routines
Table of Contents for all manual pages
Index of all manual pages