kernel-helloworld-test
diff ktestprogram/kprog.c @ 0:dbbd63da261f
helloworld kernel module and program that reads the /dev/ktest
author | Eleni Maria Stea <eleni@mutantstargoat.com> |
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date | Wed, 10 May 2017 13:11:31 +0300 |
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children |
line diff
1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000 1.2 +++ b/ktestprogram/kprog.c Wed May 10 13:11:31 2017 +0300 1.3 @@ -0,0 +1,28 @@ 1.4 +#include <fcntl.h> 1.5 +#include <stdio.h> 1.6 +#include <unistd.h> 1.7 + 1.8 +int main(void) 1.9 +{ 1.10 + char buf[512]; 1.11 + size_t size; 1.12 + int fd; 1.13 + 1.14 + if((fd = open("/dev/ktest", O_RDONLY)) == -1) { 1.15 + fprintf(stderr, "Failed to open device ktest.\n"); 1.16 + return 1; 1.17 + } 1.18 + 1.19 + if((size = read(fd, buf, sizeof buf)) == -1) { 1.20 + fprintf(stderr, "Failed to read from device ktest.\n"); 1.21 + 1.22 + close(fd); 1.23 + return 1; 1.24 + } 1.25 + printf("num char: %d\n", (int)size); 1.26 + 1.27 + buf[size] = 0; 1.28 + printf("quoting kernel: %s", buf); 1.29 + close(fd); 1.30 + return 0; 1.31 +}