diff --git a/src/variable.cpp b/src/variable.cpp
index 5d23b4d1b5..79543f9a71 100644
--- a/src/variable.cpp
+++ b/src/variable.cpp
@@ -31,6 +31,7 @@
 #include "random_mars.h"
 #include "region.h"
 #include "thermo.h"
+#include "tokenizer.h"
 #include "universe.h"
 #include "update.h"
 
@@ -5112,19 +5113,17 @@ int VarReader::read_scalar(char *str)
 
   if (me == 0) {
     while (1) {
-      if (fgets(str,MAXLINE,fp) == nullptr) n = 0;
-      else n = strlen(str);
-      if (n == 0) break;                                 // end of file
-      str[n-1] = '\0';                                   // strip newline
-      if ((ptr = strchr(str,'#'))) *ptr = '\0';          // strip comment
-      str += strspn(" \t\n\r\f");                        // strip whitespace
-      str[strcspn(str," \t\n\r\f")] = '\0';
-      n = strlen(str) + 1;
-      if (n == 1) continue;                              // skip if blank
+      ptr = fgets(str,MAXLINE,fp);
+      if (!ptr) { n=0; break; }             // end of file
+      ptr[strcspn(ptr,"#")] = '\0';         // strip comment
+      ptr += strspn(ptr," \t\n\r\f");       // strip leading whitespace
+      ptr[strcspn(ptr," \t\n\r\f")] = '\0'; // strip trailing whitespace
+      n = strlen(ptr) + 1;
+      if (n == 1) continue;                 // skip if blank line
       break;
     }
+    memmove(str,ptr,n);                       // move trimmed string back
   }
-
   MPI_Bcast(&n,1,MPI_INT,0,world);
   if (n == 0) return 1;
   MPI_Bcast(str,n,MPI_CHAR,0,world);
@@ -5157,22 +5156,20 @@ int VarReader::read_peratom()
   char str[MAXLINE];
   if (me == 0) {
     while (1) {
-      if (fgets(str,MAXLINE,fp) == nullptr) n = 0;
-      else n = strlen(str);
-      if (n == 0) break;                                 // end of file
-      str[n-1] = '\0';                                   // strip newline
-      if ((ptr = strchr(str,'#'))) *ptr = '\0';          // strip comment
-      str += strspn(" \t\n\r\f");                        // strip whitespace
-      str[strcspn(str," \t\n\r\f")] = '\0';
-      n = strlen(str) + 1;
-      if (n == 1) continue;                              // skip if blank
+      ptr = fgets(str,MAXLINE,fp);
+      if (!ptr) { n=0; break; }             // end of file
+      ptr[strcspn(ptr,"#")] = '\0';         // strip comment
+      ptr += strspn(ptr," \t\n\r\f");       // strip leading whitespace
+      ptr[strcspn(ptr," \t\n\r\f")] = '\0'; // strip trailing whitespace
+      n = strlen(ptr) + 1;
+      if (n == 1) continue;                 // skip if blank line
       break;
     }
+    memmove(str,ptr,n);                     // move trimmed string back
   }
 
   MPI_Bcast(&n,1,MPI_INT,0,world);
   if (n == 0) return 1;
-
   MPI_Bcast(str,n,MPI_CHAR,0,world);
   bigint nlines = utils::bnumeric(FLERR,str,false,lmp);
   tagint map_tag_max = atom->map_tag_max;
@@ -5187,9 +5184,17 @@ int VarReader::read_peratom()
     for (i = 0; i < nchunk; i++) {
       next = strchr(buf,'\n');
       *next = '\0';
-      int rv = sscanf(buf,TAGINT_FORMAT " %lg",&tag,&value);
-      if (tag <= 0 || tag > map_tag_max || rv != 2)
-        error->one(FLERR,"Invalid atom ID in variable file");
+      try {
+        ValueTokenizer words(buf);
+        tag = words.next_bigint();
+        value = words.next_double();
+      } catch (TokenizerException &e) {
+        error->all(FLERR,fmt::format("Invalid atomfile line '{}': {}",
+                                     buf,e.what()));
+      }
+      if ((tag <= 0) || (tag > map_tag_max))
+        error->all(FLERR,fmt::format("Invalid atom ID {} in variable "
+                                     "file", tag));
       if ((m = atom->map(tag)) >= 0) vstore[m] = value;
       buf = next + 1;
     }