# PetscFunctionListAdd
Given a routine and a string id, saves that routine in the specified registry. 
## Synopsis
```
#include <petscsys.h>
PetscErrorCode PetscFunctionListAdd(PetscFunctionList *flist,const char name[],void (*fptr)(void))
```
Not Collective


## Input Parameters

- ***flist -*** pointer to function list object
- ***name -*** string to identify routine
- ***fptr -*** function pointer



## Notes
To remove a registered routine, pass in a NULL fptr.

Users who wish to register new classes for use by a particular PETSc
component (e.g., `SNES`) should generally call the registration routine
for that particular component (e.g., `SNESRegister()`) instead of
calling `PetscFunctionListAdd()` directly.




## See Also
 `PetscFunctionListDestroy()`, `SNESRegister()`, `KSPRegister()`,
`PCRegister()`, `TSRegister()`, `PetscFunctionList`, `PetscObjectComposeFunction()`

## Level
developer

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/sys/dll/reg.c.html#PetscFunctionListAdd">src/sys/dll/reg.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex74.c.html">src/ksp/ksp/tutorials/ex74.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex11.c.html">src/ts/tutorials/ex11.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex11_sa.c.html">src/ts/tutorials/ex11_sa.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex8.c.html">src/ts/tutorials/ex8.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex9.c.html">src/ts/tutorials/ex9.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/utils/dmplexlandau/tutorials/ex2.c.html">src/ts/utils/dmplexlandau/tutorials/ex2.c.html</A><BR>


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