io_open()

int io_open ( resmgr_context_t *ctp,
              io_open_t *msg,
              RESMGR_HANDLE_T *handle,
              void *extra ) 

Classification: Connect

Default handler: iofunc_open_default()

Helper functions: iofunc_ability_check(), iofunc_ocb_attach(), iofunc_open()

Client functions: open(), fopen(), sopen() (and others)

Messages: _IO_CONNECT with one of _IO_CONNECT_COMBINE, _IO_CONNECT_COMBINE_CLOSE or _IO_CONNECT_OPEN subtypes.

Data structure:

struct _io_connect {
  // internal fields (as described above)
  uint16_t path_len;
  uint8_t  extra_type;
  uint16_t extra_len;
  char     path [1];
};

struct _io_connect_link_reply {
  uint32_t reserved1;
  uint32_t file_type;
  uint8_t  eflag;
  uint8_t  reserved2[1];
  uint16_t chroot_len;
  uint32_t umask;
  uint16_t nentries;
  uint16_t path_len;
};

typedef union {
  struct _io_connect            connect;
  struct _io_connect_link_reply link_reply;
} io_open_t;

Description: This is the main entry point into the resource manager. It checks that the client indeed has the appropriate permissions to open the file, binds the OCB to the internal library structures (via resmgr_bind_ocb(), or iofunc_ocb_attach()), and returns an errno. Note that not all input and output structure members are relevant for this function.

Returns: The status via the helper macro _IO_SET_CONNECT_RET().