| commit | author | age | ||
| b8e5f6 | 1 | /* |
| G | 2 | * Copyright (C) 2024 LingYun IoT System Studio |
| 3 | * Author: Guo Wenxue <guowenxue@gmail.com> | |
| 4 | * | |
| 5 | * A character skeleton driver test code in user space. | |
| 6 | */ | |
| 7 | ||
| 8 | #include <stdio.h> | |
| 9 | #include <unistd.h> | |
| 10 | #include <string.h> | |
| 11 | #include <errno.h> | |
| 12 | #include <sys/types.h> | |
| 13 | #include <sys/stat.h> | |
| 14 | #include <fcntl.h> | |
| 15 | ||
| 16 | int main (int argc, char **argv) | |
| 17 | { | |
| 18 | char *devname = "/dev/chrdev0"; | |
| 19 | char buf[1024]; | |
| 20 | int rv = 0; | |
| 21 | int fd; | |
| 22 | ||
| 23 | fd = open(devname, O_RDWR); | |
| 24 | if( fd < 0 ) | |
| 25 | { | |
| 26 | printf("Open device %s failed: %s\n", devname, strerror(errno)); | |
| 27 | return 1; | |
| 28 | } | |
| 29 | ||
| 30 | rv = write(fd, "Hello", 5); | |
| 31 | if( rv< 0) | |
| 32 | { | |
| 33 | printf("Write data into device failed, rv=%d: %s\n", rv, strerror(errno)); | |
| 34 | rv = 2; | |
| 35 | goto cleanup; | |
| 36 | } | |
| 37 | printf("Write %d bytes data okay\n", rv); | |
| 38 | ||
| 39 | memset(buf, 0, sizeof(buf)); | |
| 40 | rv = read(fd, buf, sizeof(buf)); | |
| 41 | if( rv< 0) | |
| 42 | { | |
| 43 | printf("Read data from device failed, rv=%d: %s\n", rv, strerror(errno)); | |
| 44 | rv = 3; | |
| 45 | goto cleanup; | |
| 46 | } | |
| 47 | printf("Read %d bytes data: %s\n", rv, buf); | |
| 48 | ||
| 49 | cleanup: | |
| 50 | close(fd); | |
| 51 | return rv; | |
| 52 | } | |
