int nPrefix = (int)strlen(zPrefix);
  for(i=FOSSIL_FIRST_CMD; i<MX_COMMAND; i++){
    if( strncmp(zPrefix, aCommand[i].zName, nPrefix)==0 ){
      blob_appendf(pList, " %s", aCommand[i].zName);
    }
  }
}

/*
** Return the index of the first non-space character that follows
** a span of two or more spaces.  Return 0 if there is not gap.
*/
static int hasGap(const char *z, int n){
  int i;
  for(i=3; i<n-1; i++){
    if( z[i]==' ' && z[i+1]!=' ' && z[i-1]==' ' ) return i+1;
  }
  return 0 ;
}

/*
** Append text to pOut, adding formatting markup.  Terms that
** have all lower-case letters are within <tt>..</tt>.  Terms
** that have all upper-case letters are within <i>..</i>.
*/
static void appendMixedFont(Blob *pOut, const char *z, int n){
  const char *zEnd = "";
  int i = 0;
  int j;
  while( i<n ){
    if( z[i]==' ' ){
      for(j=i+1; j<n && z[j]==' '; j++){}
      blob_append(pOut, z+i, j-i);
      i = j;
    }else{
      for(j=i; j<n && z[j]!=' ' && !fossil_isalpha(z[j]); j++){}
      if( j>=n || z[j]==' ' ){
        zEnd = "";
      }else{
        if( fossil_isupper(z[j]) ){
          blob_append(pOut, "<i>",3);
          zEnd = "</i>";
        }else{
          blob_append(pOut, "<tt>", 4);
          zEnd = "</tt>";
        }
      }
      while( j<n && z[j]!=' ' ){ j++; }
      blob_appendf(pOut, "%#h", j-i, z+i);
      if( zEnd[0] ) blob_append(pOut, zEnd, -1);
      i = j;
    }
  }
}

/*
** Attempt to reformat plain-text help into HTML for display on a webpage.
**
** The HTML output is appended to Blob pHtml, which should already be
** initialized.
**
** Formatting rules:
**
**   *  Bullet lists are indented from the surrounding text by
**      at least one space.  Each bullet begins with " * ".
**
**   *  Display lists are indented from the surrounding text.
**      Each tag begins with "-" or occur on a line that is
**      followed by two spaces and a non-space.  <dd> elements can begin
**      on the same line as long as they are separated by at least
**      two spaces.
**
**   *  Indented text is show verbatim (<pre>...</pre>)
*/
static void help_to_html(const char *zHelp, Blob *pHtml){
  int i;
  char *s;
  char *d;
  char *z;
  char c;
  int nIndent = 0;
  int wantP = 0;
  int wantBR = 0;
  int aIndent[10];
  const char *azEnd[10];
  int iLevel = 0;
  int isLI = 0;
  static const char *zEndDL = "</dl></blockquote>";
  static const char *zEndPRE = "</pre></blockquote>";
  static const char *zEndUL = "</ul>";
  static const char *zEndDD = "</dd>";

  /* Transform "%fossil" into just "fossil" */
  z = s = d = mprintf("%s", zHelp);
  while( *s ){
    if( *s=='%' && strncmp(s, "%fossil", 7)==0 ){
      s++;
  aIndent[0] = 0;
  azEnd[0] = "";
  while( zHelp[0] ){
    i = 0;
    while( (c = zHelp[i])!=0
        && c!='\n'
        && (c!='%' || strncmp(zHelp+i,"%fossil",7)!=0)
    ){ i++; }
    if( c=='%' ){
      if( i ) blob_appendf(pHtml, "%#h", i, zHelp);
      zHelp += i + 1;
      i = 0;
      wantBR = 1;
      continue;
    }
    for(nIndent=0; nIndent<i && zHelp[nIndent]==' '; nIndent++){}
    if( nIndent==i ){
      if( c==0 ) break;
      blob_append(pHtml, "\n", 1);
      wantP = 1;
      wantBR = 0;
      zHelp += i+1;
      continue;
    }
    if( nIndent+2<i && zHelp[nIndent]=='*' && zHelp[nIndent+1]==' ' ){
      nIndent += 2;
      while( nIndent<i && zHelp[nIndent]==' '){ nIndent++; }
      isLI = 1;
    }else{
      *d++ = *s++;
    }
  }
  *d = 0;

  blob_appendf(pHtml, "<pre>\n%h\n</pre>\n", z);
  fossil_free(z);
      isLI = 0;
    }
    while( iLevel>0 && aIndent[iLevel]>nIndent ){
      blob_append(pHtml, azEnd[iLevel--], -1);
    }
    if( nIndent>aIndent[iLevel] ){
      assert( iLevel<ArraySize(aIndent)-2 );
      if( isLI ){
        iLevel++;
        aIndent[iLevel] = nIndent;
        azEnd[iLevel] = zEndUL;
        blob_append(pHtml, "<ul>\n", 5);
      }else if( zHelp[nIndent]=='-' || hasGap(zHelp+nIndent,i-nIndent) ){
        iLevel++;
        aIndent[iLevel] = nIndent;
        azEnd[iLevel] = zEndDL;
        blob_append(pHtml, "<blockquote><dl>\n", -1);
      }else if( wantP && azEnd[iLevel]!=zEndDL ){
        iLevel++;
        aIndent[iLevel] = nIndent;
        azEnd[iLevel] = zEndPRE;
        blob_append(pHtml, "<blockquote><pre>", -1);
        wantP = 0;
      }
    }
    if( isLI ){
      blob_append(pHtml, "<li> ", 5);
    }
    if( wantP ){
      blob_append(pHtml, "<p> ", 4);
      wantP = 0;
    }
    if( azEnd[iLevel]==zEndDL ){
      int iDD;
      blob_append(pHtml, "<dt> ", 5);
      iDD = hasGap(zHelp+nIndent, i-nIndent);
      if( iDD ){
        int x;
        assert( iLevel<ArraySize(aIndent)-1 );
        iLevel++;
        aIndent[iLevel] = x = nIndent+iDD;
        azEnd[iLevel] = zEndDD;
        appendMixedFont(pHtml, zHelp+nIndent, iDD-2);
        blob_appendf(pHtml, "</dt><dd>%#h\n", x, zHelp+x);
      }else{
        appendMixedFont(pHtml, zHelp+nIndent, i-nIndent);
        blob_append(pHtml, "</dt>\n", 6);
      }
    }else if( wantBR ){
      appendMixedFont(pHtml, zHelp+nIndent, i-nIndent);
      blob_append(pHtml, "<br>\n", 5);
      wantBR = 0;
    }else{
      blob_appendf(pHtml, "%#h\n", i-nIndent, zHelp+nIndent);
    }
    zHelp += i+1;
    i = 0;
    if( c==0 ) break;
  }
  while( iLevel>0 ){
    blob_appendf(pHtml, "%s\n", azEnd[iLevel--]);
  }
}

/*
** Format help text for TTY display.
*/
static void help_to_text(const char *zHelp, Blob *pText){
  int i;
  char c;
  for(i=0; (c = zHelp[i])!=0; i++){
    if( c=='%' && strncmp(zHelp+i,"%fossil",7)==0 ){
      if( i>0 ) blob_append(pText, zHelp, i);
      blob_append(pText, "fossil", 6);
      zHelp += i+7;
      i = -1;
      continue;
    }
    if( c=='\n' && strncmp(zHelp+i+1,">  ",3)==0 ){
      if( i>0 ) blob_append(pText, zHelp, i-1);
      blob_append(pText, "  ", 6);
      zHelp += i+3;
      i = -1;
      continue;
    }
  }
  if( i>0 ){
    blob_append(pText, zHelp, i);
  }      
}

/*
** COMMAND: test-all-help
**
** Usage: %fossil test-all-help ?OPTIONS?
**

    fossil_print("-->\n");
    fossil_print("<!-- start_all_help -->\n");
  }else{
    fossil_print("---\n");
  }
  for(i=0; i<MX_COMMAND; i++){
    if( (aCommand[i].eCmdFlags & mask)==0 ) continue;
    fossil_print("# %s\n", aCommand[i].zName);
    if( useHtml ){
      Blob html;
      blob_zero(&html);
      blob_init(&html, 0, 0);
      help_to_html(aCommand[i].zHelp, &html);
      fossil_print("<h1>%h</h1>\n", aCommand[i].zName);
      fossil_print("%s\n\n", blob_str(&html));
      fossil_print("%s\n<hr>\n", blob_str(&html));
      blob_reset(&html);
    }else{
      Blob txt;
      blob_init(&txt, 0, 0);
      help_to_text(aCommand[i].zHelp, &txt);
      fossil_print("# %s\n", aCommand[i].zName);
      fossil_print("%s\n\n", aCommand[i].zHelp);
      fossil_print("%s\n\n", blob_str(&txt));
      blob_reset(&txt);
    }
  }
  if( useHtml ){
    fossil_print("<!-- end_all_help -->\n");
  }else{
    fossil_print("---\n");
  }

@   --utc                   Display times using UTC
@   --vfs NAME              Cause SQLite to use the NAME VFS
;

/*
** COMMAND: help
**
** Usage: %fossil help TOPIC
** Usage: %fossil help [OPTIONS] [TOPIC]
**    or: %fossil TOPIC --help
**
** Display information on how to use TOPIC, which may be a command, webpage, or
** setting.  Webpage names begin with "/".  To display a list of available
** topics, use one of:
** setting.  Webpage names begin with "/".  If TOPIC is omitted, a list of
** topics is returned.
**
** The following options can be used when TOPIC is omitted:
**    %fossil help                Show common commands
**    %fossil help -a|--all       Show both common and auxiliary commands
**    %fossil help -o|--options   Show command-line options common to all cmds
**    %fossil help -s|--setting   Show setting names
**    %fossil help -t|--test      Show test commands only
**    %fossil help -x|--aux       Show auxiliary commands only
**    %fossil help -w|--www       Show list of webpages
**
**    -a|--all          List both command and auxiliary commands
**    -o|--options      List command-line options common to all commands
**    -s|--setting      List setting names
**    -t|--test         List unsupported "test" commands
**    -x|--aux          List only auxiliary commands
**    -w|--www          List all web pages
**
** These options can be used when TOPIC is present:
**
**    -h|--html         Format output as HTML rather than plain text
*/
void help_cmd(void){
  int rc;
  int isPage = 0;
  const char *z;
  const char *zCmdOrPage;
  const CmdOrPage *pCmd = 0;
  int useHtml = 0;
  Blob txt;
  if( g.argc<3 ){
    z = g.argv[0];
    fossil_print(
      "Usage: %s help TOPIC\n"
      "Common commands:  (use \"%s help help\" for more options)\n",
      z, z);
    command_list(0, CMDFLAG_1ST_TIER);

    command_list(0, CMDFLAG_TEST);
    return;
  }
  else if( find_option("setting","s",0) ){
    command_list(0, CMDFLAG_SETTING);
    return;
  }
  useHtml = find_option("html","h",0)!=0;
  isPage = ('/' == *g.argv[2]) ? 1 : 0;
  if(isPage){
    zCmdOrPage = "page";
  }else{
    zCmdOrPage = "command or setting";
  }
  rc = dispatch_name_search(g.argv[2], CMDFLAG_ANY|CMDFLAG_PREFIX, &pCmd);

  }
  if( pCmd->eCmdFlags & CMDFLAG_SETTING ){
    fossil_print("Setting: \"%s\"%s\n\n",
         pCmd->zName,
         (pCmd->eCmdFlags & CMDFLAG_VERSIONABLE)!=0 ? " (versionable)" : ""
    );
  }
  while( *z ){
    if( *z=='%' && strncmp(z, "%fossil", 7)==0 ){
      fossil_print("%s", g.argv[0]);
  blob_init(&txt, 0, 0);
  if( useHtml ){
    help_to_html(z, &txt);
      z += 7;
    }else{
  }else{
      putchar(*z);
      z++;
    }
    help_to_text(z, &txt);
  }
  }
  putchar('\n');
  fossil_print("%s\n", blob_str(&txt));
  blob_reset(&txt);
}

/*
** Return a pointer to the setting information array.
**
** This routine provides access to the aSetting2[] array which is created
** by the mkindex utility program and included with <page_index.h>.