What does struct { .attr = value } syntax mean?

Question

From fuse/examples/fsel.c

static struct fuse_operations fsel_oper = {
    .getattr    = fsel_getattr,
    .readdir    = fsel_readdir,
    .open       = fsel_open,
    .release    = fsel_release,
    .read       = fsel_read,
    .poll       = fsel_poll,
};

this is the definitionof fuse_operations

struct fuse_operations_compat25 {
    int (*getattr) (const char *, struct stat *);
    int (*readlink) (const char *, char *, size_t);
    int (*getdir) (const char *, fuse_dirh_t, fuse_dirfil_t);
    int (*mknod) (const char *, mode_t, dev_t);
    int (*mkdir) (const char *, mode_t);
    int (*unlink) (const char *);
    int (*rmdir) (const char *);
    .....
};

so what do those . mean? It's the first time I see that

http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html – Maroun May 20 '13 at 17:04 — Maroun, May 20 '13 at 17:04
Initialization that it specify a member. – BLUEPIXY May 20 '13 at 17:05 — BLUEPIXY, May 20 '13 at 17:05

score 1 · Accepted Answer · answered May 20 '13 at 17:04

1

It means that the field that is named after the . will have that value.

For example, the gettr function pointer will point to the fsel_getattr function.

answered May 20 '13 at 17:04

Tom

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and what happens with non-initialized values? are they set to 0? – Lacrymology May 20 '13 at 17:10

What does struct { .attr = value } syntax mean?

1 Answers1