Basic Syscall API
Collaboration diagram for Basic Syscall API:
|
Functions | |
| int | a4l_sys_open (const char *fname) |
| Open an Analogy device. More... | |
| int | a4l_sys_close (int fd) |
| Close an Analogy device. More... | |
| int | a4l_sys_read (int fd, void *buf, size_t nbyte) |
| Read from an Analogy device. More... | |
| int | a4l_sys_write (int fd, void *buf, size_t nbyte) |
| Write to an Analogy device. More... | |
Detailed Description
Function Documentation
| int a4l_sys_close | ( | int | fd | ) |
Close an Analogy device.
- Parameters
-
[in] fd File descriptor as returned by a4l_sys_open()
- Returns
- 0 on success, otherwise a negative error code.
Referenced by a4l_close(), and a4l_open().
| int a4l_sys_open | ( | const char * | fname | ) |
Open an Analogy device.
- Parameters
-
[in] fname Device name
- Returns
- Positive file descriptor value on success, otherwise a negative error code.
Referenced by a4l_open().
| int a4l_sys_read | ( | int | fd, |
| void * | buf, | ||
| size_t | nbyte | ||
| ) |
Read from an Analogy device.
The function a4l_read() is only useful for acquisition configured through an Analogy command.
- Parameters
-
[in] fd File descriptor as returned by a4l_sys_open() [out] buf Input buffer [in] nbyte Number of bytes to read
- Returns
- Number of bytes read. Otherwise:
- -EINVAL is returned if some argument is missing or wrong (Please, type "dmesg" for more info)
- -ENOENT is returned if the device's reading subdevice is idle (no command was sent)
- -EFAULT is returned if a user <-> kernel transfer went wrong
- -EINTR is returned if calling task has been unblocked by a signal
Referenced by a4l_async_read().
| int a4l_sys_write | ( | int | fd, |
| void * | buf, | ||
| size_t | nbyte | ||
| ) |
Write to an Analogy device.
The function a4l_write() is only useful for acquisition configured through an Analogy command.
- Parameters
-
[in] fd File descriptor as returned by a4l_sys_open() [in] buf Output buffer [in] nbyte Number of bytes to write
- Returns
- Number of bytes written. Otherwise:
- -EINVAL is returned if some argument is missing or wrong (Please, type "dmesg" for more info)
- -ENOENT is returned if the device's writing subdevice is idle (no command was sent)
- -EFAULT is returned if a user <-> kernel transfer went wrong
- -EINTR is returned if calling task has been unblocked by a signal
Referenced by a4l_async_write().
