n = dispatch_approx_match(g.argv[i], 20, az);
    for(j=0; j<n; j++){
      fossil_print("   %s\n", az[j]);
    }
  }
}


/*
** Returns 1 if the command or page name zName is known to be a
** command/page which is only available in certain builds/platforms,
** else returns 0.
*/
static int help_is_platform_command(const char *zName){
  const char *aList[] = {
    /* List of commands/pages which are known to only be available in
    ** certain builds/platforms. */
    "winsrv",
    "json", "/json",
    NULL /* end-of-list sentinel */
  };
  int i = 0;
  const char *z;
  for( z = aList[0]; z ; z = aList[++i] ){
    if( 0==fossil_strcmp(zName, z) ) return 1;
  }
  return 0;
}

/*
** WEBPAGE: help
** URL: /help?name=CMD
**
** Show the built-in help text for CMD.  CMD can be a command-line interface
** command or a page name from the web interface or a setting.
** Query parameters:

      @ <h1>The "%h(pCmd->zName)" page:</h1>
    }else if( rc==0 && (pCmd->eCmdFlags & CMDFLAG_SETTING)!=0 ){
      @ <h1>The "%h(pCmd->zName)" setting:</h1>
    }else{
      @ <h1>The "%h(pCmd->zName)" command:</h1>
    }
    if( rc==1 || (rc==2 && zCmd[0]=='/') ){
      if( zCmd && help_is_platform_command(zCmd) ){
        @ Not available in this build: "%h(zCmd)"
      }else{
        @ Unknown topic: "%h(zCmd)"
      }
    }else if( rc==2 ){
      @ Ambiguous prefix: "%h(zCmd)"
    }else{
      if( pCmd->zHelp[0]==0 ){
        @ No help available for "%h(pCmd->zName)"
      }else if( P("plaintext") ){
        Blob txt;

    zCmdOrPage = "command or setting";
  }
  rc = dispatch_name_search(g.argv[2], mask|CMDFLAG_PREFIX, &pCmd);
  if( rc ){
    int i, n;
    const char *az[5];
    if( rc==1 ){
      if( help_is_platform_command(g.argv[2]) ){
        fossil_print("Command is not available in this build: %s\n", g.argv[2]);
        return;
      }
      fossil_print("unknown %s: %s\n", zCmdOrPage, g.argv[2]);
    }else{
      fossil_print("ambiguous %s prefix: %s\n",
                 zCmdOrPage, g.argv[2]);
    }
    fossil_print("Did you mean one of these TOPICs:\n");
    n = dispatch_approx_match(g.argv[2], 5, az);