Change #version '<>' operator to '!='.

Tweak error messages a little.

lesskey.nro.VER

@@ -367,7 +367,7 @@ This can be helpful if a lesskey file is used by different versions of
 For example, suppose that a new command named 'sideways-search' is added in version 777.
 Then the following line would assign the command to the Q key, but only in versions of
 .I less
-which support it. The line would be ignored in earlier versions.
+which support it. The line would be ignored by earlier versions.
 .sp
 .nf
  #version >= 777 Q sideways-search
@@ -382,11 +382,12 @@ l l.
  >= Greater than or equal to
  <= Less than or equal to
  = Equal to
- <> Not equal to
+ != Not equal to
 .TE
 .RE
 .sp
-In version 594 and earlier, all #version lines are ignored,
+Due to lack of both foresight and time travel,
+all #version lines are ignored in version 594 and all earlier versions, 
 regardless of the result of the relational operator.
 .
 .SH "SEE ALSO"

lesskey_parse.c

@@ -127,13 +127,14 @@ static struct lesskey_cmdname editnames[] =
  * Print a parse error message.
  */
  static void
-parse_error(s1, s2)
- char *s1;
- char *s2;
+parse_error(fmt, arg1)
+ char *fmt;
+ char *arg1;
 {
  char buf[1024];
+ int n = snprintf(buf, sizeof(buf), "%s: line %d: ", lesskey_file, linenum);
+ snprintf(buf+n, sizeof(buf)-n, fmt, arg1);
  ++errors;
- snprintf(buf, sizeof(buf), "%s: line %d: %s%s", lesskey_file, linenum, s1, s2);
  lesskey_parse_error(buf);
 }
 
@@ -237,7 +238,7 @@ tstr(pp, xlate)
  case 'X': ch = SK_CTL_DELETE; break;
  case '1': ch = SK_F1; break;
  default: { char buf[2]; buf[0] = *p; buf[1] = '\0';
- parse_error("illegal escape sequence \\k", buf);
+ parse_error("invalid escape sequence \"\\k%s\"", buf);
  *pp = p+1;
  return (""); }
  }
@@ -374,7 +375,7 @@ match_version(op, ver)
  case '!': return less_version != ver;
  default: {
  char sop[2] = { op, '\0' };
- parse_error("invalid operator in #version: ", sop);
+ parse_error("invalid operator '%s' in #version", sop);
  return 0; }
  }
 }
@@ -396,24 +397,19 @@ version_line(s, tables)
  s += strlen("#version");
  s = skipsp(s);
  op = *s++;
- if (op == '<' && *s == '=')
- {
- op = '-';
- s++;
- } else if (op == '>' && *s == '=')
- {
- op = '+';
- s++;
- } else if (op == '<' && *s == '>')
+ /* Simplify 2-char op to one char. */
+ switch (op)
  {
- op = '!';
- s++;
+ case '<': if (*s == '=') { s++; op = '-'; } break;
+ case '>': if (*s == '=') { s++; op = '+'; } break;
+ case '=': if (*s == '=') { s++; } break;
+ case '!': if (*s == '=') { s++; } break;
  }
  s = skipsp(s);
  ver = lstrtoi(s, &e);
  if (e == s)
  {
- parse_error("invalid version number in #version: ", s);
+ parse_error("non-numeric version number in #version", "");
  return (NULL);
  }
  if (!match_version(op, ver))
@@ -472,7 +468,7 @@ findaction(actname, tables)
  for (i = 0; tables->currtable->names[i].cn_name != NULL; i++)
  if (strcmp(tables->currtable->names[i].cn_name, actname) == 0)
  return (tables->currtable->names[i].cn_action);
- parse_error("unknown action: ", actname);
+ parse_error("unknown action: \"%s\"", actname);
  return (A_INVALID);
 }
 
@@ -573,7 +569,7 @@ parse_varline(line, tables)
  p = skipsp(p);
  if (*p++ != '=')
  {
- parse_error("missing = in: ", line);
+ parse_error("missing = in variable definition", "");
  return;
  }
 
@@ -647,7 +643,7 @@ parse_lesskey(infile, tables)
  desc = stdin;
  else if ((desc = fopen(infile, "r")) == NULL)
  {
- /* parse_error("cannot open lesskey file ", infile); */
+ /* parse_error("cannot open lesskey file %s", infile); */
  return (-1);
  }