Simple implementation of Linux programming more commands

The more command has three uses:

1.more filename

2.command | More

3.more < filename

This example is used when using./more_1 execution can also copy more_1 to/bin file, equivalent to adding a new command

more_1.c

#include <stdio.h> #include <stdlib.h> #include <string.h> #define LINE_LENGTH 512#define page_length    24int See_more (file* fp_cmd) {if (Fp_cmd = = NULL) printf ("Error stop\n");    Char ch; printf ("\033[7m more?        \033[m ");//vt100 programming, detailed reference on-line while ((ch = getc (fp_cmd)) = NULL)//Read {if (ch = = ' Q ') return 0 from the terminal;        if (ch = = ") return page_length;;    if (ch = = ' \ n ') return 1; } return 0;}    void Do_more (file* fp) {int line_num = 0;    Char Line_buf[line_length];    int reply;    File* Fp_tty;    if (Fp_tty = fopen ("/dev/tty", "r") = = NULL)//parentheses are used, no amplification will be wrong perror ("open TTY error!\n"); while (Fgets (LINE_BUF,LINE_LENGTH,FP)) {if (Line_num = = page_length) {reply =                See_more (Fp_tty);                if (reply = = 0) break;                if (reply = = page_length) line_num = 0; if (reply = = 1) liNe_num--;            } if (fputs (line_buf,stdout) = = EOF) exit (-1);        line_num++; } fclose (Fp_tty);}    int main (int argc,char* argv[]) {file* fp; if (argc = = 1) {printf ("Usage:more [-DFLPCSU] [+linenum |        +/pattern] name1 name2 ... \ n ");    Exit (0);                } else {while (--ARGC) {fp = fopen (* ++argv, "R");                    if (fp! = NULL) {do_more (FP);                Fclose (FP);            } else Perror ("Open eror!\n"); }        }}

Legacy issue: Anti-white display with case input bounce display

Percent display

To press ENTER to execute

We'll do it later.

Simple implementation of Linux programming more commands