SCO OpenServer

iowait(D3oddi)

iowait -- wait for I/O completion

Synopsis

void iowait(struct buf bp);

Description

Called by the kernel to wait for the completion of a block I/O operation.

Arguments

bp: Pointer to the buf structure that specifies the I/O operation.

Return value

No value is returned.

Usage

The iowait( ) function is called by the higher levels of the kernel I/O system to wait for the completion of a block I/O operation. Drivers do not generally call this function, although it could be called from the halt(D2oddi) entry point routine if necessary.

Drivers must call the iodone(D3oddi) function when the I/O operation is completed. The calling process continues when the I/O operation is complete. iowait( ) is only used in block drivers for I/O operations that are executed by the strategy(D2oddi) entry point routine.

iowait( ) transfers any errors found in bp->b_error to u.u_error for the process indicated in the buf header.

iowait( ) cannot be interrupted by signals.

Context and synchronization

User or blockable context.

Hardware applicability

All

Version applicability

oddi: 1, 2, 2mp, 3, 3mp, 4, 4mp, 5, 5mp, 6, 6mp

SVR5 DDI compatibility

The biowait(D3) functions provides similar functionality for DDI drivers. DDI drivers can also call biowait_sig(D3) for a block that can be interrupted by a signal.

References

brelse(D3oddi), iodone(D3oddi), sleep(D3oddi)