Map a logical filesystem offset to a physical filesystem or device offset
#include <sys/dcmd_blk.h> #define DCMD_FSYS_MAP_OFFSET __DIOTF(_DCMD_FSYS, 21, union fs_blkmap)
Argument | Value |
---|---|
filedes | A file descriptor that you obtained by opening the device. |
dcmd | DCMD_FSYS_MAP_OFFSET |
dev_data_ptr | A pointer to a union fs_blkmap |
n_bytes | sizeof(union fs_blkmap) |
dev_info_ptr | NULL |
This command maps a logical filesystem offset to a physical filesystem or device offset, depending on the flag specified in the input. It uses a union fs_blkmap for both input and output:
union fs_blkmap { struct { off64_t logical; uint32_t flags; } i; struct { off64_t physical; uint32_t nbytes; } o; };
The i (input) member includes:
The o (output) member includes:
The devctl() function can return the following, in addition to the error codes listed in its entry in the C Library Reference:
devctl() in the QNX Neutrino C Library Reference