hello.c

#define FUSE_USE_VERSION  26#include <fuse.h>#include <stdio.h>#include <string.h>#include <errno.h>#include <fcntl.h>static const char *hello_str = "Hello World!\n";static const char *hello_path = "/hello";static int hello_getattr(const char *path, struct stat *stbuf){    int res = 0;    memset(stbuf, 0, sizeof(struct stat));    if(strcmp(path, "/") == 0) {        stbuf->st_mode = S_IFDIR | 0755;        stbuf->st_nlink = 2;    }    else if(strcmp(path, hello_path) == 0) {        stbuf->st_mode = S_IFREG | 0444;        stbuf->st_nlink = 1;        stbuf->st_size = strlen(hello_str);    }    else        res = -ENOENT;    return res;}static int hello_readdir(const char *path, void *buf, fuse_fill_dir_t filler,                         off_t offset, struct fuse_file_info *fi){    (void) offset;    (void) fi;    if(strcmp(path, "/") != 0)        return -ENOENT;    filler(buf, ".", NULL, 0);    filler(buf, "..", NULL, 0);    filler(buf, hello_path + 1, NULL, 0);    return 0;}static int hello_open(const char *path, struct fuse_file_info *fi){    if(strcmp(path, hello_path) != 0)        return -ENOENT;    if((fi->flags & 3) != O_RDONLY)        return -EACCES;    return 0;}static int hello_read(const char *path, char *buf, size_t size, off_t offset,                      struct fuse_file_info *fi){    size_t len;    (void) fi;    if(strcmp(path, hello_path) != 0)        return -ENOENT;    len = strlen(hello_str);    if (offset < len) {        if (offset + size > len)            size = len - offset;        memcpy(buf, hello_str + offset, size);    } else        size = 0;    return size;}static struct fuse_operations hello_oper = {    .getattr    = hello_getattr,    .readdir    = hello_readdir,    .open       = hello_open,    .read       = hello_read,};int main(int argc, char *argv[]){    return fuse_main(argc, argv, &hello_oper, NULL);}