replace '\_' with '_' in plain text where possible

                             # no default value

The executable created by CMake (after running make) is named *lmp* unless

the LAMMPS\_MACHINE option is set.  When setting `LAMMPS_MACHINE=name`

the executable will be named *lmp\_name*\.  Using `BUILD\_MPI=no` will

the LAMMPS_MACHINE option is set.  When setting `LAMMPS_MACHINE=name`

the executable will be named *lmp_name*\.  Using `BUILD_MPI=no` will

enforce building a serial executable using the MPI STUBS library.

**Traditional make**\ :

   make mybox              # uses Makefile.mybox to produce lmp_mybox

Any "make machine" command will look up the make settings from a file

Makefile.machine, create a folder Obj\_machine with all objects and

generated files and an executable called *lmp\_machine*\ .  The standard

Makefile.machine, create a folder Obj_machine with all objects and

generated files and an executable called *lmp_machine*\ .  The standard

parallel build with `make mpi` assumes a standard MPI installation with

MPI compiler wrappers where all necessary compiler and linker flags to

get access and link with the suitable MPI headers and libraries are set

by the wrapper programs.  For other cases or the serial build, you have

to adjust the make file variables MPI\_INC, MPI\_PATH, MPI\_LIB as well

to adjust the make file variables MPI_INC, MPI_PATH, MPI_LIB as well

as CC and LINK.  To enable OpenMP threading usually a compiler specific

flag needs to be added to the compile and link commands.  For the GNU

compilers, this is *-fopenmp*\ , which can be added to the CC and LINK

.. note::

   The file STUBS/mpi.c provides a CPU timer function called

   MPI\_Wtime() that calls gettimeofday() .  If your operating system

   MPI_Wtime() that calls gettimeofday() .  If your operating system

   does not support gettimeofday() , you will need to insert code to

   call another timer.  Note that the ANSI-standard function clock()

   rolls over after an hour or so, and is therefore insufficient for

<Packages_details>` doc page for more info on these packages and the doc

pages for their respective commands for OpenMP threading info.

For CMake, if you use BUILD\_OMP=yes, you can use these packages and

For CMake, if you use BUILD_OMP=yes, you can use these packages and

turn on their native OpenMP support and turn on their native OpenMP

support at run time, by setting the OMP\_NUM\_THREADS environment

support at run time, by setting the OMP_NUM_THREADS environment

variable before you launch LAMMPS.

For building via conventional make, the CCFLAGS and LINKFLAGS

In those case, all 'default(none)' directives (which aid in detecting

incorrect and unwanted sharing) can be replaced with 'default(shared)'

while dropping all 'shared()' directives. The script

'src/USER-OMP/hack\_openmp\_for\_pgi\_gcc9.sh' can be used to automate

'src/USER-OMP/hack_openmp_for_pgi_gcc9.sh' can be used to automate

this conversion.

----------

   -D LAMMPS_LIB_SUFFIX=name    # name = mpi, serial, mybox, titan, laptop, etc

                                # no default value

Setting BUILD\_EXE=no will not produce an executable.  Setting

BUILD\_LIB=yes will produce a static library named *liblammps.a*\ .

Setting both BUILD\_LIB=yes and BUILD\_SHARED\_LIBS=yes will produce a

shared library named *liblammps.so* instead. If LAMMPS\_LIB\_SUFFIX is

Setting BUILD_EXE=no will not produce an executable.  Setting

BUILD_LIB=yes will produce a static library named *liblammps.a*\ .

Setting both BUILD_LIB=yes and BUILD_SHARED_LIBS=yes will produce a

shared library named *liblammps.so* instead. If LAMMPS_LIB_SUFFIX is

set to *name* in addition, the name of the generated libraries will be

changed to either *liblammps\_name.a* or *liblammps\_name.so*\ ,

changed to either *liblammps_name.a* or *liblammps_name.so*\ ,

respectively.

**Traditional make**\ :

   make mode=shlib machine    # build LAMMPS shared lib liblammps_machine.so

   make mode=shexe machine    # same as "mode=exe" but uses objects from "mode=shlib"

The two "exe" builds will generate and executable *lmp\_machine*\ ,

while the two library builds will create a file *liblammps\_machine.a*

or *liblammps\_machine.so*\ . They will also create generic soft links,

The two "exe" builds will generate and executable *lmp_machine*\ ,

while the two library builds will create a file *liblammps_machine.a*

or *liblammps_machine.so*\ . They will also create generic soft links,

named *liblammps.a* and *liblammps.so*\ , which point to the specific

*liblammps\_machine.a/so* files.

*liblammps_machine.a/so* files.

**CMake and make info**\ :

This will install the lammps executable and library (if requested), some

tools (if configured) and additional files like library API headers,

manpages, potential and force field files. The location of the installation

tree is set by the CMake variable "CMAKE\_INSTALL\_PREFIX" which defaults

tree is set by the CMake variable "CMAKE_INSTALL_PREFIX" which defaults

to ${HOME}/.local

----------

All the LAMMPS-specific -D variables that a LAMMPS build supports are

described on the pages linked to from the :doc:`Build <Build>` doc page.

All of these variable names are upper-case and their values are

lower-case, e.g. -D LAMMPS\_SIZES=smallbig.  For boolean values, any of

lower-case, e.g. -D LAMMPS_SIZES=smallbig.  For boolean values, any of

these forms can be used: yes/no, on/off, 1/0.

On Unix/Linux machines, CMake generates a Makefile by default to

you try it first when building LAMMPS in those cases.

The commands below perform a default LAMMPS build, producing the LAMMPS

executable lmp\_serial and lmp\_mpi in lammps/src:

executable lmp_serial and lmp_mpi in lammps/src:

.. code-block:: bash