pSOSystem System Calls - Read

pSOS+ System Calls de_close
de_close Closes an I/O device.
#include
unsigned long de_close(
unsigned long dev, /* major/minor device number */
void *iopb, /* I/O parameter block address */
void *retval /* return value */
)
Description
Arguments
Return Code
The de_close() call invokes the device close routine of a pSOS+ device driver
specified by the dev argument. The functionality of the device close routine is
device-specific. For example, an RS-232 device driver close-routine may signal a
modem to hang up to signify the end of the connection.
The de_close() call, when used in conjunction with de_open(), can also be used
to implement mutual exclusion. In this case, de_close() can be used to signal the
end of a critical region for the device operation.
dev Specifies the major and minor device numbers, which are
stored in the upper and lower 16 bits, respectively.
iopb Points to an I/O parameter block, the contents of which are
driver-specific.
retval Points to a variable that receives a driver-specific value
returned by the driver.
This call returns 0 on success, or an error code on failure. Besides the error codes
listed below, other driver-specific errors may be returned.
pSOSystem System Calls 1-11
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