diff options
Diffstat (limited to 'disk-utils/raw.8')
| -rw-r--r-- | disk-utils/raw.8 | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/disk-utils/raw.8 b/disk-utils/raw.8 index 6fbdb8558..dbd44e7b2 100644 --- a/disk-utils/raw.8 +++ b/disk-utils/raw.8 @@ -15,6 +15,11 @@ raw \- bind a Linux raw character device .PP .B raw .B \-qa +.SH WARNING +The rawio is a deprecated interface since Linux kernel 2.6.3. Please, +modify your application to open the block device with the +O_DIRECT flag. + .SH DESCRIPTION .B raw is used to bind a Linux raw character device to a block device. Any @@ -75,10 +80,12 @@ With .B -h provides a usage summary. .SH BUGS -The Linux +The Linux .B dd -(1) command does not currently align its buffers correctly, and so -cannot be used on raw devices. +(1) command should be used without bs= option or the blocksize needs to be a +multiple of the sector size of the device (512 bytes usually) otherwise it +will fail with "Invalid Argument" messages (EINVAL). + .PP Raw I/O devices do not maintain cache coherency with the Linux block device buffer cache. If you use raw I/O to overwrite data already in |