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/* See LICENSE file for copyright and license details. */
#include <fcntl.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include "util.h"
#define COLUMNS 80
#define ROWS 25
#define BUFSIZE 10
static void
usage(void)
{
eprintf("usage: %s [file ...]\n", argv0);
}
int
main(int argc, char *argv[])
{
int fd;
char c;
int col;
int row;
int buf[BUFSIZE];
ARGBEGIN {
default:
usage();
} ARGEND
if (argc < 1 && isatty(STDIN_FILENO)) {
usage();
}
if (isatty(STDIN_FILENO)) {
if ((fd = open(*argv, O_RDONLY)) < 0) {
weprintf("open %s:", *argv);
return 0;
}
} else {
fd = STDIN_FILENO;
}
col = 0;
row = 0;
while (read(fd, &c, 1) != 0) {
switch (c) {
case '\r':
col = 0;
break;
case '\n':
col = 0;
row++;
break;
case '\t':
col = ((col+1) | 0x07)+1;
break;
case '\b':
if (col>0) {
col--;
}
break;
default:
col++;
break;
}
putchar(c);
if (row<ROWS) {
continue;
}
puts("--more--");
if (read(STDIN_FILENO, &buf, BUFSIZE) < 0) {
goto END;
}
col = 0;
row = 0;
}
END:
if (fd > STDERR_FILENO) {
close(fd);
}
return 0;
}
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