from dolfin import *
from dolfin_utils import meshconvert

dolfin-convert cylinder6.msh out.xml

$ dolfin-convert
Usage: dolfin-convert [OPTIONS] ... input.x output.y

Options:

  -h         display this help text and exit
  -i format  specify input format
  -o format  specify output format

Alternatively, the following long options may be used:

  --help     same as -h
  --input    same as -i
  --output   same as -o

Supported formats:

  xml      - DOLFIN XML mesh format (current)
  xml-old  - DOLFIN XML mesh format (DOLFIN 0.6.2 and earlier)
  mesh     - Medit, generated by tetgen with option -g
  Triangle - Triangle file format (input prefix of .ele and .node files)
  gmsh     - Gmsh, version 2.0 file format
  metis    - Metis graph file format
  scotch   - Scotch graph file format
  diffpack - Diffpack tetrahedral grid format
  abaqus   - Abaqus tetrahedral grid format
  ExodusII - Sandia Format (requires ncdump utility from NetCDF)
  Star-CD  - Star-CD tetrahedral grid format

If --input or --output are not specified, the format will
be deduced from the suffix:

  .xml  - xml
  .mesh - mesh
  .gmsh - gmsh
  .msh  - gmsh
  .gra  - metis
  .grf  - scotch
  .grid - diffpack
  .inp  - abaqus
  .e    - Exodus II
  .exo  - Exodus II
  .ncdf - ncdump'ed Exodus II
  .vrt and .cell  - starcd

from dolfin_utils import meshconvert

# Convert to XML
meshconvert.convert2xml(ifilename, ofilename, iformat=iformat)

# Order mesh
os.system("dolfin-order %s" % ofilename)

import os
os.system('dolfin-convert carbon_f.msh mesh.xml')

meshio-convert cylinder6.msh out.xml