Performs a read operation on an open file with arguments passed in iovec elements.
#include <sys/types.h> #include <sys/errno.h>
int fp_readv (fp, iov, iovcnt, ext, segflag, countp) struct file *fp; char *iov; int iovcnt; int ext; int segflag; int *countp;
|fp||Points to a file structure returned by the fp_open kernel service.|
|iov||Points to an array of iovec elements. Each iovec element describes a buffer where data to be read from the file is to be stored.|
|iovcnt||Specifies the number of iovec elements in the array pointed to by the iov parameter.|
|ext||Specifies an extension argument required by some device drivers. Its content, form, and use are determined by the individual driver.|
|segflag|| Indicates in which part of memory the array specified by the iov
|countp||Points to the location where the count of bytes actually read from the file is to be returned.|
The fp_readv kernel service is an internal interface to the function provided by the readv subroutine.
The fp_readv kernel service can be called from the process environment only.
|0||Indicates a successful operation.|
If an error occurs, one of the values from the /usr/include/sys/errno.h file is returned.
The fp_readv kernel service is part of Base Operating System (BOS) Runtime.
The readv subroutine.
Logical File System Kernel Services in AIX Version 4.3 Kernel Extensions and Device Support Programming Concepts.