status.i4.v = fm_io(vun.i2.r, io_buffer.g.v, num_bytes.i4.r
status.i4.v = fm_io_c(vun.i2.v, io_buffer.g.v, num_bytes.i4.v
This routine will read or write a Filesharing record opened on
the virtual unit number. The file may have either sequential or
relative organization and fixed or variable length records.
If the file was opened with direct access, the logical record
number defines the record to be read. If the file was opened
with sequential access, the next record in sequence is accessed.
vun virtual unit number on which the file was opened
io_buffer user's data buffer to be read or written
num_bytes number of bytes to be read or written. If "num_bytes"
is less than zero, the record will be read. If it's
greater than zero, the record will be written.
[record_number] specifies the logical record number for files
opened for direct access (default is 0)
[ext_status] returned extended status from VMS/RMS (default is NULL)
This function returns ACNET status values as follows:
FSHARE_xxx error accessing file
CBS_INVARG zero byte length
This function requires the following include files:
cnsparam_h, cbslib_h, acnet_errors_h
fm_read(_c), fm_write(_c), fm_open_io(_c), fm_open_read(_c),
int num_bytes = NUM_BYTES;
int record_number = RECORD_NUMBER;
status = fm_io_c(vun,(void *) io_buffer,num_bytes,record_number,