fstatvfs (BPX1FTV, BPX4FTV) — Get the file system status
Function
The fstatvfs callable service obtains status information about a file system. The file system is specified by a file descriptor that refers to a file from the desired file system.
Requirements
Operation | Environment |
---|---|
Authorization: | Supervisor state or problem state, any PSW key |
Dispatchable unit mode: | Task |
Cross memory mode: | PASN = HASN |
AMODE (BPX1FTV): | 31-bit |
AMODE (BPX4FTV): | 64-bit |
ASC mode: | Primary mode |
Interrupt status: | Enabled for interrupts |
Locks: | Unlocked |
Control parameters: | All parameters must be addressable by the caller and in the primary address space. |
Format
|
AMODE 64 callers use BPX4FTV with the same parameters.
Parameters
- File_descriptor
- Supplied parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword that contains the file descriptor for the file.
- Status_area_length
- Supplied parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword that contains the length of the area to which the service returns status information.
- Status_area
- Parameter supplied and returned
- Type:
- Structure
- Length:
- Specified by the Status_area_length parameter
The name of an area of length Status_area_length to which the service returns the status information for the file system. The BPXYSSTF macro maps this area. For information on this macro, see BPXYSSTF — Map response structure for file system status.
- Return_value
- Returned parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword in which the fstatvfs service returns the length of the status written to the Status_area if the request is successful, or -1 if it is not successful.
- Return_code
- Returned parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword in which the fstatvfs service stores the return code. The fstatvfs service returns Return_code only if Return_value is -1. See z/OS UNIX System Services Messages and Codes for a complete list of possible return code values. The fstatvfs service can return one of the following values in the Return_code parameter:Return_code Explanation EAGAIN Information is temporarily unavailable. This can occur because the mount process for the file system is incomplete. EBADF The File_descriptor parameter does not specify a valid, open file descriptor. EINVAL Parameter error; for example, Status_area_length is too small. The following reason code can accompany the return code: JRBuffTooSmall. - Reason_code
- Returned parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword where the fstatvfs service stores the reason code. The fstatvfs service returns Reason_code only if Return_value is -1. Reason_code further qualifies the Return_code value. For the reason codes, see z/OS UNIX System Services Messages and Codes.
Usage notes
- If the passed Status_area_length is not less than or equal to zero, it is not considered an error for the Status_area_length to be insufficient to hold the requested information. (In other words, future expansion is allowed for.) As much information as can fit is written to Status_area, and this amount is returned.
- The amount of valid data returned in the Status_area is indicated by the Return_value. This allows for differences in the release levels of z/OS UNIX and the physical file systems.
Related services
Characteristics and restrictions
There are no restrictions on the use of the fstatvfs service.
Examples
For an example using this callable service, see BPX1FTV (fstatvfs) example.