自己实现more命令

 #include    <stdio.h>
 #include    <stdlib.h>

 #define PAGELEN 24
 #define LINELEN 512

 int see_more(FILE*);
 void do_more(FILE*);

 int main(int ac, char* av[])
 {
     FILE *fp;
     if(ac==)
         do_more(stdin);
     //    printf("%s","Please input file name.\n");
     else
     {
         while(--ac)
         if((fp=fopen(*++av,"r"))!=NULL)
         {
             do_more(fp);
             fclose(fp);
         }
     }

 }

 void do_more(FILE* fp)
 {
     int num_of_lines=;
     char line[LINELEN];
     int reply;
 //    int see_more();
     FILE* fp_tty;
     fp_tty=fopen("/dev/tty","r");
     if(fp_tty==NULL) exit();
     while(fgets(line,LINELEN,fp))
     {
         if(num_of_lines==PAGELEN)
         {
             reply=see_more(fp_tty);
             if(reply==)
                 break;
             num_of_lines-=reply;
         }
         if(fputs(line,stdout)==EOF)
             exit();
         num_of_lines++;
     }

 }

 int see_more(FILE* cmd)
 {
     int c;
     //printf("\033[7m more? \033[m");
     printf("\033[32;49;1m [more?] \033[39;49;0m");
     //033[32;49;1m [MORE?] \033[39;49;0m
     while((c=getc(cmd))!=EOF)
     {
         if(c=='q')
             return ;

         if(c=='\n')
             return ;

         if(c==' ')
             return PAGELEN;
     }
 }