help.c

用c写的ftp客户端源代码,可以在UNIX,Windows下编译通过,学习的好代码!

/* dftp: FTP client example
 * Copyright (c) 1996 by Donald C. Asonye
 * Email: [e-mail]
 *
 * help.c
 *
 * This and other files are hereby released	to the public for 
 * educational purposes.  You may redistribute this and other files
 * or routines as long as you are not compensated for it, and as 
 * long as this notice is included with it.  You may not use the 
 * released source codes in anyway commercial without permission.
 *
 * It'd be nice if you share your modifications with me and everyone
 * else.  I encourage you to make the code better as I am very busy.
 *
 * Share your knowledge :)
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "help.h"

/*
 * help 
 * general help function.  you can specify more than one command
 * you want help on.  i.e: help put get ls
 */
void help( char *command )
{
   char *hstr;

   (void)strtok(command," ");
   hstr=strtok((char *)NULL," ");

   if( !hstr || ! *hstr)
       HelpIndex();
   else {
       ExecHelp(hstr);
       while( (hstr=strtok((char *)NULL," ")) != NULL) 
	  ExecHelp(hstr);
   }
}

/*
 * display all commands supported.
 * a lot of commands still needs to be implemented.
 * you should try implementing them. 
 */

void HelpIndex(void)
{
printf("                      Help Topics\n\
 !     ascii  binary bye    cd     close     dir   exit     get\n\
 lcd   lls    ldir   open   put    quit      rhelp\n");
}

/*
 * show help on a command
 * :(( this will be a long function
 */
void ExecHelp( char *command)
{

 if( !strcmp(command,"!") )
     printf("!<command>          execute system command\n");
 else if( !strcmp(command,"ascii") || !strcmp(command,"as") )
     printf("ascii|as            set file trasfer mode to ascii\n");
 else if( !strcmp(command,"binary") || !strcmp(command,"bin") )
     printf("binary|bin          set file transfer mode to binary\n");
 else if( !strcmp(command,"bye") )
     printf("bye                 terminate connection and exit\n");
 else if( !strcmp(command,"cd") )
     printf("cd <remote-dir.>    change remote working directory\n");
 else if( !strcmp(command,"close") )
     printf("close               close connection without quiting\n");
 else if( !strcmp(command,"dir") )
     printf("dir                 get remote directory listing\n");
 else if( !strcmp(command, "exit") )
     printf("exit                terminate connection and exit\n");
 else if( !strcmp(command, "get") )
     printf("get <remote-file>   retrieve a remote file\n");
 else if( !strcmp(command, "lcd"))
     printf("lcd <local-dir.>    change local working directory\n");
 else if(!strcmp(command,"lls") || !strcmp(command,"ldir") )
     printf("lls|ldir            get local directory listing\n");
 else if( !strcmp(command, "ls") )
     printf("ls [options]        get remote directory listing\n");
 else if( !strcmp(command, "open") )
     printf("open <host|ip>      open connection to server\n");
 else if(!strcmp(command, "put") )
     printf("put <local-file>    send local file to remote host\n");
 else if( !strcmp(command, "pwd") )
     printf("pwd                 get remote current working \
directory\n");
 else if( !strcmp(command, "quit") )
     printf("quit                terminate connection and exit\n");
 else if( !strcmp(command, "rhelp") )
     printf("rhelp [command]     get remote help\n");
 else if( !strcmp(command, "user") )
     printf("user <username>     send new user information\n\
		     you will be prompted for password\n");
 else
     printf("Invalid command\n");
}