FMS File Parameter IOWARN
Data Type
Integer
Default Value
0
DESCRIPTION:
This parameter provides additional options to the FMS file system. Most of these options may be used to debug your application when performing direct I/O.
The value of IWARN you specify is obtained by adding together the numeric value of each option you select. Because these numeric values are a power of 2, they have the effect of setting bits in IWARN.
- 0
No warning messages are printed.
When performing direct I/O, FMS increases the transfer length if required.
- +1
Stop FMS if a condition is found that voilates the requirements for direct I/O. You must also select one of the warning message tests listed below: (+4), (+8), (+16).
- +2
Do not increase the lenght of transfers, even if the requested length does not satisfy the conditions for direct I/O.
- +4
Print a warning message containing "DIO" if the transfer length requested does not satisfy the conditions for direct I/O. Note that by default, FMS automatically increases the transfer lenght if required. However this may have undesirable side effects if insufficient space was allocated on disk or in memory.
- +8
Print a warning message containing "DIO" if the starting disk address does not satisfy the conditions for direct I/O.
- +16
Print a warning message containing "DIO" if the starting memory address does not satisfy the conditions for direct I/O.
- +1024
Do not print properties of removable disks.
This option is useful in Windows systems when the removable media is not present.
A typical use of this Parameter is as follows:
- Add the following two lines to the license file:
IOTYPE=2
IOWARN=28
- Run your application, directing the output to a file, myout.txt.
./myapp > myout.txt
- Search for warning messages:
grep DIO myout.txt
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