T2345: After examining comments changed by batch conversion of NULL

to nullptr, I've corrected a small number where it seemed clear
that the previous NULL should have been either "NULL" (where the
code is looking for a string with that value),  or null char / null byte
(where the comment is talking about the char/byte that terminates
a c-style string).

Also changed 6 places where the batch change had changed 'NULL ptr'
to 'nullptr ptr'. Now they simply say 'nullptr'.

src/GPU/pair_eam_alloy_gpu.cpp

@@ -324,7 +324,7 @@ void PairEAMAlloyGPU::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/GPU/pair_eam_fs_gpu.cpp

@@ -324,7 +324,7 @@ void PairEAMFSGPU::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/KOKKOS/pair_eam_alloy_kokkos.cpp

@@ -938,7 +938,7 @@ void PairEAMAlloyKokkos<DeviceType>::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/KOKKOS/pair_eam_fs_kokkos.cpp

@@ -938,7 +938,7 @@ void PairEAMFSKokkos<DeviceType>::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/MANYBODY/pair_adp.cpp

@@ -465,7 +465,7 @@ void PairADP::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/MANYBODY/pair_airebo.cpp

@@ -185,7 +185,7 @@ void PairAIREBO::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to C and H
-  // map[i] = which element (0,1) the Ith atom type is, -1 if nullptr
+  // map[i] = which element (0,1) the Ith atom type is, -1 if "NULL"
 
   for (int i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/MANYBODY/pair_airebo.h

@@ -40,7 +40,7 @@ class PairAIREBO : public Pair {
   enum { AIREBO, REBO_2, AIREBO_M }; // for telling class variants apart in shared code
 
 protected:
-  int *map;                        // 0 (C), 1 (H), or -1 (nullptr) for each type
+  int *map;                        // 0 (C), 1 (H), or -1 ("NULL") for each type
 
   int variant;
   int ljflag,torflag;              // 0/1 if LJ/Morse,torsion terms included

src/MANYBODY/pair_comb.cpp

@@ -456,7 +456,7 @@ void PairComb::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/MANYBODY/pair_comb3.cpp

@@ -192,7 +192,7 @@ void PairComb3::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/MANYBODY/pair_eam_alloy.cpp

@@ -70,7 +70,7 @@ void PairEAMAlloy::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/MANYBODY/pair_eam_fs.cpp

@@ -70,7 +70,7 @@ void PairEAMFS::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/MANYBODY/pair_eim.cpp

@@ -388,7 +388,7 @@ void PairEIM::coeff(int narg, char **arg)
   read_file(arg[2+nelements]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3 + nelements; i < narg; i++) {
     m = i - (3+nelements) + 1;

src/MANYBODY/pair_gw.cpp

@@ -283,7 +283,7 @@ void PairGW::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/MANYBODY/pair_lcbop.cpp

@@ -135,8 +135,8 @@ void PairLCBOP::coeff(int narg, char **arg)
   if (strcmp(arg[0],"*") != 0 || strcmp(arg[1],"*") != 0)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
-  // read args that map atom types to C and nullptr
-  // map[i] = which element (0 for C) the Ith atom type is, -1 if nullptr
+  // read args that map atom types to C and "NULL"
+  // map[i] = which element (0 for C) the Ith atom type is, -1 if "NULL"
 
   for (int i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/MANYBODY/pair_lcbop.h

@@ -39,7 +39,7 @@ class PairLCBOP : public Pair {
 
  protected:
   int **pages;                     // neighbor list pages
-  int *map;                        // 0 (C) or -1 (nullptr) for each type
+  int *map;                        // 0 (C) or -1 ("NULL") for each type
 
   int me;
 

src/MANYBODY/pair_nb3b_harmonic.cpp

@@ -198,7 +198,7 @@ void PairNb3bHarmonic::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/MANYBODY/pair_polymorphic.cpp

@@ -479,7 +479,7 @@ void PairPolymorphic::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/MANYBODY/pair_sw.cpp

@@ -262,7 +262,7 @@ void PairSW::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/MANYBODY/pair_tersoff.cpp

@@ -306,7 +306,7 @@ void PairTersoff::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/MANYBODY/pair_vashishta.cpp

@@ -269,7 +269,7 @@ void PairVashishta::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-COLVARS/fix_colvars.cpp

@@ -961,7 +961,7 @@ void FixColvars::write_restart(FILE *fp)
     proxy->serialize_status(rest_text);
     // TODO call write_output_files()
     const char *cvm_state = rest_text.c_str();
-    int len = strlen(cvm_state) + 1; // need to include terminating nullptr byte.
+    int len = strlen(cvm_state) + 1; // need to include terminating null byte.
     fwrite(&len,sizeof(int),1,fp);
     fwrite(cvm_state,1,len,fp);
   }

src/USER-INTEL/pair_eam_alloy_intel.cpp

@@ -69,7 +69,7 @@ void PairEAMAlloyIntel::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/USER-INTEL/pair_eam_fs_intel.cpp

@@ -69,7 +69,7 @@ void PairEAMFSIntel::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/USER-MEAMC/pair_meamc.cpp

@@ -556,7 +556,7 @@ void PairMEAMC::read_files(const std::string &globalfile,
   delete [] rozero;
   delete [] found;
 
-  // done if user param file is nullptr
+  // done if user param file is "NULL"
 
   if (userfile == "NULL") return;
 

src/USER-MISC/pair_agni.cpp

@@ -266,7 +266,7 @@ void PairAGNI::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-MISC/pair_drip.cpp

@@ -139,7 +139,7 @@ void PairDRIP::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-MISC/pair_edip.cpp

@@ -779,7 +779,7 @@ void PairEDIP::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-MISC/pair_edip_multi.cpp

@@ -539,7 +539,7 @@ void PairEDIPMulti::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-MISC/pair_extep.cpp

@@ -467,7 +467,7 @@ void PairExTeP::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-MISC/pair_ilp_graphene_hbn.cpp

@@ -167,7 +167,7 @@ void PairILPGrapheneHBN::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-MISC/pair_kolmogorov_crespi_full.cpp

@@ -168,7 +168,7 @@ void PairKolmogorovCrespiFull::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-MISC/pair_kolmogorov_crespi_z.cpp

@@ -232,7 +232,7 @@ void PairKolmogorovCrespiZ::coeff(int narg, char **arg)
   utils::bounds(FLERR,arg[1],1,atom->ntypes,jlo,jhi,error);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-MISC/pair_lebedeva_z.cpp

@@ -228,7 +228,7 @@ void PairLebedevaZ::coeff(int narg, char **arg)
   utils::bounds(FLERR,arg[1],1,atom->ntypes,jlo,jhi,error);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-MISC/pair_meam_spline.cpp

@@ -398,7 +398,7 @@ void PairMEAMSpline::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-MISC/pair_meam_sw_spline.cpp

@@ -393,7 +393,7 @@ void PairMEAMSWSpline::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-MISC/pair_tersoff_table.cpp

@@ -755,7 +755,7 @@ void PairTersoffTable::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/USER-OMP/pair_eam_alloy_omp.cpp

@@ -69,7 +69,7 @@ void PairEAMAlloyOMP::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/USER-OMP/pair_eam_fs_omp.cpp

@@ -69,7 +69,7 @@ void PairEAMFSOMP::coeff(int narg, char **arg)
   read_file(arg[2]);
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   for (i = 3; i < narg; i++) {
     if (strcmp(arg[i],"NULL") == 0) {

src/USER-REAXC/pair_reaxc.cpp

@@ -327,7 +327,7 @@ void PairReaxC::coeff( int nargs, char **args )
   }
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
 
   int itmp = 0;
   int nreax_types = system->reax_param.num_atom_types;

src/USER-SMTBQ/pair_smtbq.cpp

@@ -277,7 +277,7 @@ void PairSMTBQ::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/atom.cpp

@@ -2201,10 +2201,10 @@ void Atom::add_callback(int flag)
   int ifix;
 
   // find the fix
-  // if find nullptr ptr:
+  // if find nullptr:
   //   it's this one, since it is being replaced and has just been deleted
   //   at this point in re-creation
-  // if don't find nullptr ptr:
+  // if don't find nullptr:
   //   i is set to nfix = new one currently being added at end of list
 
   for (ifix = 0; ifix < modify->nfix; ifix++)

src/fix_spring_rg.cpp

@@ -67,7 +67,7 @@ void FixSpringRG::init()
 {
   masstotal = group->mass(igroup);
 
-  // if rg0 was specified as nullptr, compute current Rg
+  // Compute current Rg
   // only occurs on 1st run
 
   if (rg0_flag) {

src/input.cpp

@@ -467,10 +467,10 @@ char *Input::nextword(char *str, char **next)
   //   start = first char beyond quote
   //   stop = first char of matching quote
   //   next = first char beyond matching quote
-  //   next must be nullptr or whitespace
+  //   next must be null char or whitespace
   // if start is not single/double/triple quote:
   //   stop = first whitespace char after start
-  //   next = char after stop, or stop itself if stop is nullptr
+  //   next = char after stop, or stop itself if stop is null char
 
   if (strstr(start,"\"\"\"") == start) {
     stop = strstr(&start[3],"\"\"\"");
@@ -492,7 +492,7 @@ char *Input::nextword(char *str, char **next)
     else *next = stop+1;
   }
 
-  // set stop to nullptr to terminate word
+  // set stop to null char to terminate word
 
   *stop = '\0';
   return start;
@@ -510,9 +510,9 @@ void Input::substitute(char *&str, char *&str2, int &max, int &max2, int flag)
   // use str2 as scratch space to expand str, then copy back to str
   // reallocate str and str2 as necessary
   // do not replace $ inside single/double/triple quotes
-  // var = pts at variable name, ended by nullptr
-  //   if $ is followed by '{', trailing '}' becomes nullptr
-  //   else $x becomes x followed by nullptr
+  // var = pts at variable name, ended by null char
+  //   if $ is followed by '{', trailing '}' becomes null char
+  //   else $x becomes x followed by null char
   // beyond = points to text following variable
 
   int i,n,paren_count;

src/pair_coul_streitz.cpp

@@ -143,7 +143,7 @@ void PairCoulStreitz::coeff(int narg, char **arg)
     error->all(FLERR,"Incorrect args for pair coefficients");
 
   // read args that map atom types to elements in potential file
-  // map[i] = which element the Ith atom type is, -1 if nullptr
+  // map[i] = which element the Ith atom type is, -1 if "NULL"
   // nelements = # of unique elements
   // elements = list of element names
 

src/read_dump.cpp

@@ -713,7 +713,7 @@ void ReadDump::read_atoms()
 
       if (nnew > maxnew || maxnew == 0) {
         memory->destroy(fields);
-        maxnew = MAX(nnew,1);    // avoid nullptr ptr
+        maxnew = MAX(nnew,1);    // avoid nullptr
         memory->create(fields,maxnew,nfield,"read_dump:fields");
       }
 
@@ -753,7 +753,7 @@ void ReadDump::read_atoms()
       nnew = static_cast<int> (olast - ofirst);
       if (nnew > maxnew || maxnew == 0) {
         memory->destroy(fields);
-        maxnew = MAX(nnew,1);     // avoid nullptr ptr
+        maxnew = MAX(nnew,1);     // avoid nullptr
         memory->create(fields,maxnew,nfield,"read_dump:fields");
       }
 
@@ -779,7 +779,7 @@ void ReadDump::read_atoms()
     nnew = static_cast<int> (sum);
     if (nnew > maxnew || maxnew == 0) {
       memory->destroy(fields);
-      maxnew = MAX(nnew,1);     // avoid nullptr ptr
+      maxnew = MAX(nnew,1);     // avoid nullptr
       memory->create(fields,maxnew,nfield,"read_dump:fields");
     }
 
@@ -1105,7 +1105,7 @@ void ReadDump::migrate_new_atoms()
   Irregular *irregular = new Irregular(lmp);
   int nrecv = irregular->create_data(nnew,procassign,1);
   int newmaxnew = MAX(nrecv,maxnew);
-  newmaxnew = MAX(newmaxnew,1);    // avoid nullptr ptr
+  newmaxnew = MAX(newmaxnew,1);    // avoid nullptr
   memory->create(newfields,newmaxnew,nfield,"read_dump:newfields");
   irregular->exchange_data((char *) &fields[0][0],nfield*sizeof(double),
                            (char *) &newfields[0][0]);

src/run.cpp

@@ -91,7 +91,7 @@ void Run::command(int narg, char **arg)
 
       // all remaining args are commands
       // first,last = arg index of first/last commands
-      // set ncommands = 0 if single command and it is nullptr
+      // set ncommands = 0 if single command and it is "NULL"
 
     } else if (strcmp(arg[iarg],"every") == 0) {
       if (iarg+3 > narg) error->all(FLERR,"Illegal run command");