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#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <fcntl.h>
int main(int argc, char** argv) {
printf("PID: %d\n", getpid());
int fd = syscall(SYS_openat, -100, "testfile", O_RDWR);
printf("Openat ret: %d\n", fd);
if (fd == -1) {
printf("Opneat error: %s\n", strerror(errno));
}
int ret = syscall(SYS_write, fd, "I'm writing this :) pls.", 24);
printf("Write ret: %d\n", ret);
if (ret == -1) {
printf("Write error: %s\n", strerror(errno));
}
ret = syscall(SYS_write, fd, "\nplease", 7);
printf("Write ret: %d\n", ret);
if (ret == -1) {
printf("Write error: %s\n", strerror(errno));
}
ret = syscall(SYS_lseek, fd, 0, SEEK_SET);
printf("FSeek ret: %d\n", ret);
if (ret == -1) {
printf("FSeek error: %s\n", strerror(errno));
}
ret = syscall(SYS_write, fd, "A", 1);
printf("Write ret: %d\n", ret);
if (ret == -1) {
printf("Write error: %s\n", strerror(errno));
}
ret = syscall(SYS_close, fd);
printf("Close ret: %d\n", ret);
if (ret == -1) {
printf("Close error: %s\n", strerror(errno));
}
return 0;
}
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