[SOLVED] Why the variables can start with a .

dspjm · 09-08-2011, 09:26 AM

As the title suggests, when I am reading source code of linux programs, there is some code like

Code:

struct context main_ctx __attribute__((section (".initctx"))) = {
    .gdt_base = (uint32_t) gdt,
    .gdt_limit = GDT_LIMIT,
    .cs = FLAT_CS,
    .ds = FLAT_DS,
    .es = FLAT_DS,
    .fs = FLAT_DS,
    .gs = FLAT_DS,
    .ss = FLAT_DS,
    .esp = (uint32_t) ESP_LOC(&main_ctx),
    .eip = (uint32_t) start_main,
    .return_addr = (uint32_t) __exit_context,
};

isn't it that the variable cant start with a .?

dwhitney67 · 09-08-2011, 09:53 AM

Those .<whatever> are the individual members of a struct definition.

For example:

Code:

struct Foo
{
   int   value;
   char* str;
};

struct Foo somefoo = {
                        .str   = "Hello World",
                        .value = 20
                     };

P.S. You may want to follow this thread, which also was posted this morning concerning a similar topic: http://www.linuxquestions.org/questi...2/#post4465557

dspjm · 09-08-2011, 10:16 AM

Quote:

Originally Posted by dwhitney67

Those .<whatever> are the individual members of a struct definition.

For example:

Code:

struct Foo
{
   int   value;
   char* str;
};

struct Foo somefoo = {
                        .str   = "Hello World",
                        .value = 20
                     };

P.S. You may want to follow this thread, which also was posted this morning concerning a similar topic: http://www.linuxquestions.org/questi...2/#post4465557

Thank you very much, it does help...^_^