AAC Microtec Sirius OBC, Руководство пользователя

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Document number 205065
Version Rev. N
Issue date 2019-02-04
Sirius OBC and TCM User Manual
www.aacmicrotec.com Page 100 of 174
Return value Description
>0 A file descriptor for the device.
- 1 see errno values
errno values
ENOENT Invalid filename
EEXIST Device already opened.
Table 5-6 - open flag symbols
Symbol Description
O_RDONLY Open for reading only
O_WRONLY Open writing only
O_RDWR Open for reading and writing
5.12.3.2. Function int close(…)
Closes access to the device.
Argument name Type Direction Description
fd int in File descriptor received at
open
.
Return value Description
0 Device closed successfully
-1 see errno values
errno values
EBADF The file descriptor fd is not an open file descriptor
5.12.3.3. Function off_t lseek(…)
Sets page offset for read/ write operations.
NOTE: The interface is not strictly POSIX, as the offset argument is expected to be given in
pages and not bytes.
Argument name Type Direction Description
fd int in File descriptor received at
open
.
offset off_t in Page number. ( NOTE: Not bytes!)
whence Int in Must be set to SEEK_SET.
Return value Description
offset Page number
- 1 see errno values
errno values
EBADF The file descriptor fd is not an open file descriptor
EINVAL whence is not a proper value.
EOVERFLOW The resulting file offset would overflow
off_t
.