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/* SPDX-License-Identifier: LGPL-2.1+ */
#include "config.h"
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#define BUFSIZE 1025
char buf[BUFSIZE];
int read_count = 2;
int main(int argc, char *argv[]){
if(argc < 3){
fprintf(stderr, "usage: %s <file> <count> [buffer|direct]\n", argv[0]);
exit(1);
}
char *file = argv[1];
read_count = atoi(argv[2]);
int ret = 0,sum = 0, i = 0, fd = -1;
if(argc == 4 && strncmp(argv[3], "direct",6) == 0)
fd = open(file, O_RDONLY|O_DIRECT);
else
fd = open(file, O_RDONLY);
while(i++ < read_count){
memset(buf, 0, BUFSIZE);
ret = read(fd, buf, BUFSIZE-1);
if(ret > 0){
write(STDOUT_FILENO, buf, ret);
sum += ret;
}else if(ret == 0){
printf("======read end======\n");
break;
}else{
printf("error:%d\n", errno);
break;
}
sleep(1);
}
printf("======read sum: %d======\n", sum);
if (fd >= 0)
close(fd);
return 0;
}
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