DCMD_ETFS_INFO

Get information about an embedded transaction filesystem

Synopsis:

#include <sys/dcmd_mem.h>

#define DCMD_ETFS_INFO      __DIOF(_DCMD_MEM, 105, struct etfs_info)

Arguments to devctl():

Argument Value
filedes A file descriptor that you obtained by opening the device
dcmd DCMD_ETFS_INFO
dev_data_ptr A pointer to a struct etfs_info
n_bytes sizeof(struct etfs_info)
dev_info_ptr NULL

Description:

This command gets information about the filesystem.

Input:

None.

Output:

A filled-in etfs_info structure, which is defined as: 

struct etfs_info {
        char    name[16];
        int             numblks;
        int             clusters2blk;
        int             clustersize;
        int             erase_cnt;
        int             clean_cnt;
        int             spare_cnt;
        int             filthy_cnt;
        int             inactive_cnt;
        int             xtnts_cnt;
        int             cache_cnt;
        int             devread_cnt;
        int             devwrite_cnt;
        int             cacheread_cnt;
        int             mine_cnt;
        int             copy_cnt;
        int             defrag_cnt;
        int             eccerr_cnt;
        int             chkerr_cnt;
        int             deverr_cnt;
        int             files_cnt;
        int             open_cnt;
        int             badblks_cnt;
        int             blksize;
        int             expansion[15];          /* For future expansion */
} ;

The members include:

name
The name of the device, which usually encodes a part number or size.
numblks
The number of blocks on the device.
clusters2blk
The number of clusters to a block on the device.
clustersize
The size of a cluster. Typically 1 KB or 2 KB.
erase_cnt
The number of erases on the part (while running).
clean_cnt
The number of erased blocks immediately ready for writing.
spare_cnt
The number of spare blocks.
filthy_cnt
The number of free blocks that are waiting to be erased and made clean.
inactive_cnt
The number of clusters not being used but trapped.
xtnts_cnt
The number of cache buffers.
cache_cnt
The number of cluster cache buffers.
devread_cnt
The number of cluster reads from the device.
devwrite_cnt
The number of cluster writes to the device.
cacheread_cnt
The number of cluster reads from cache.
mine_cnt
The number of mining operations to recover dead space in a block. This is how inactive clusters create filthy blocks, which become clean after being erased.
copy_cnt
The number of block-copy operations. Copies occur two ways: the first way is a read in a block that has a soft ECC error, which is an indication that the block is getting weak. The block is copied to a new fresh block and the block with the ECC error is erased. In the second way, a block with a low erase count is forced into service by copying its data to a new block and erasing and putting this block into service.
defrag_cnt
The number of files defragmented.
eccerr_cnt
The number of CRC data errors that are corrected by ECC.
chkerr_cnt
The number of CRC data errors.
deverr_cnt
The number of hard device errors. This is bad and usually indicates a hardware problem.
files_cnt
The number of files.
open_cnt
The number of open files.
badblks_cnt
The number of blocks marked as bad and taken out of service.
blksize
The block size, in bytes.

See also:

devctl() in the QNX Neutrino C Library Reference

etfsctl, fs-etfs-ram in the Utilities Reference

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