git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@1252 f3b2605a-c512-4ea7-a41b-209d697bcdaa

src/fix_print.cpp

@@ -29,15 +29,46 @@ using namespace LAMMPS_NS;
 FixPrint::FixPrint(LAMMPS *lmp, int narg, char **arg) :
   Fix(lmp, narg, arg)
 {
-  if (narg != 5) error->all("Illegal fix print command");
+  if (narg < 5) error->all("Illegal fix print command");
   nevery = atoi(arg[3]);
   if (nevery <= 0) error->all("Illegal fix print command");
 
   MPI_Comm_rank(world,&me);
 
   int n = strlen(arg[4]) + 1;
-  line = new char[n];
+  string = new char[n];
-  strcpy(line,arg[4]);
+  strcpy(string,arg[4]);
+
+  // parse optional args
+
+  fp = NULL;
+  screenflag = 1;
+
+  int iarg = 5;
+  while (iarg < narg) {
+    if (strcmp(arg[iarg],"file") == 0) {
+      if (iarg+2 > narg) error->all("Illegal fix print command");
+      if (me == 0) {
+	fp = fopen(arg[iarg+1],"w");
+	if (fp == NULL) {
+	  char str[128];
+	  sprintf(str,"Cannot open fix print file %s",arg[iarg+1]);
+	  error->one(str);
+	}
+      }
+      iarg += 2;
+    } else if (strcmp(arg[iarg],"screen") == 0) {
+      if (iarg+2 > narg) error->all("Illegal fix print command");
+      if (strcmp(arg[iarg+1],"yes") == 0) screenflag = 1;
+      else if (strcmp(arg[iarg+1],"no") == 0) screenflag = 0;
+      else error->all("Illegal fix print command");
+      iarg += 2;
+    } else error->all("Illegal fix print command");
+  }
+
+  // print header into file
+
+  if (fp && me == 0) fprintf(fp,"Fix print output for fix %s\n",id);
 
   copy = new char[MAXLINE];
   work = new char[MAXLINE];
@@ -47,9 +78,11 @@ FixPrint::FixPrint(LAMMPS *lmp, int narg, char **arg) :
 
 FixPrint::~FixPrint()
 {
-  delete [] line;
+  delete [] string;
   delete [] copy;
   delete [] work;
+
+  if (fp && me == 0) fclose(fp);
 }
 
 /* ---------------------------------------------------------------------- */
@@ -65,21 +98,22 @@ int FixPrint::setmask()
 
 void FixPrint::end_of_step()
 {
-  // make a copy of line to work on
+  // make a copy of string to work on
   // substitute for $ variables (no printing)
   // append a newline and print final copy
   // variable evaluation may invoke a compute that affects Verlet::eflag,vflag
 
   modify->clearstep_compute();
 
-  strcpy(copy,line);
+  strcpy(copy,string);
   input->substitute(copy,0);
   strcat(copy,"\n");
 
   modify->addstep_compute(update->ntimestep + nevery);
 
   if (me == 0) {
-    if (screen) fprintf(screen,copy);
+    if (screenflag && screen) fprintf(screen,copy);
-    if (logfile) fprintf(logfile,copy);
+    if (screenflag && logfile) fprintf(logfile,copy);
+    if (fp) fprintf(fp,copy);
   }
 }

src/fix_print.h

@@ -14,6 +14,7 @@
 #ifndef FIX_PRINT_H
 #define FIX_PRINT_H
 
+#include "stdio.h"
 #include "fix.h"
 
 namespace LAMMPS_NS {
@@ -26,8 +27,9 @@ class FixPrint : public Fix {
   void end_of_step();
 
  private:
-  int me;
+  int me,screenflag;
-  char *line,*copy,*work;
+  FILE *fp;
+  char *string,*copy,*work;
 };
 
 }