| .TH SG_REQUESTS "8" "January 2007" "sg3_utils\-1.23" SG3_UTILS |
| .SH NAME |
| sg_requests \- send one or more SCSI REQUEST SENSE commands |
| .SH SYNOPSIS |
| .B sg_requests |
| [\fI\-\-desc\fR] [\fI\-\-help\fR] [\fI\-\-hex\fR] [\fI\-\-num=NUM\fR] |
| [\fI\-\-raw\fR] [\fI\-\-status\fR] [\fI\-\-time\fR] [\fI\-\-verbose\fR] |
| [\fI\-\-version\fR] \fIDEVICE\fR |
| .SH DESCRIPTION |
| .\" Add any additional description here |
| .PP |
| Send REQUEST SENSE command to \fIDEVICE\fR and output the response which is |
| expected to be in sense data format. Both fixed and descriptor format are |
| supported. |
| .SH OPTIONS |
| Arguments to long options are mandatory for short options as well. |
| .TP |
| \fB\-d\fR, \fB\-\-desc\fR |
| sets the DESC bit in the REQUEST SENSE SCSI cdb. The \fIDEVICE\fR |
| should return sense data in descriptor (rather than fixed) format. This |
| will only occur if the \fIDEVICE\fR recognizes descriptor format (SPC\-3 |
| and later). If the device is pre SPC\-3 then setting a bit in a reserved |
| field may cause a check condition status with an illegal request sense key. |
| .TP |
| \fB\-h\fR, \fB\-\-help\fR |
| output the usage message then exit. |
| .TP |
| \fB\-H\fR, \fB\-\-hex\fR |
| output response in ASCII hexadecimal. |
| .TP |
| \fB\-n\fR, \fB\-\-num\fR=\fINUM\fR |
| perform \fINUM\fR SCSI REQUEST SENSE commands, stopping when either \fINUM\fR |
| is reached or an error occurs. The default value for \fINUM\fR is 1 . |
| .TP |
| \fB\-r\fR, \fB\-\-raw\fR |
| output response in binary (to stdout). |
| .TP |
| \fB\-s\fR, \fB\-\-status\fR |
| if the last REQUEST SENSE finished without error (from SCSI status or |
| autosense) then the contents of the parameter data are analysed as |
| sense data and the exit status is set accordingly. The default |
| action (when this option is not given) is to ignore the contents |
| of the parameter data for the purposes of setting the exit status. |
| Some types of error set a sense key of "NO SENSE" with non\-zero |
| information in the additional sense code (e.g. the FAILURE PREDICTION |
| THRESHOLD EXCEEDED group of codes); this results in an exit status |
| value of 10. If the sense key is "NO SENSE" and both asc and ascq are |
| zero then the exit status is set to 0 . See the sg3_utils(8) man page |
| for exit status values. |
| .TP |
| \fB\-t\fR, \fB\-\-time\fR |
| time the SCSI REQUEST SENSE command(s) and calculate the average number |
| of operations per second. |
| .TP |
| \fB\-v\fR, \fB\-\-verbose\fR |
| increase the level of verbosity, (i.e. debug output). |
| Additionally the response (if received) is output in ASCII-HEX. Use |
| this option multiple times for greater verbosity. |
| .TP |
| \fB\-V\fR, \fB\-\-version\fR |
| print the version string and then exit. |
| .SH NOTES |
| In SCSI 1 and 2 the REQUEST SENSE command was very important for error |
| and warning processing in SCSI. The autosense capability rendered this |
| command almost superfluous. |
| .PP |
| However recent SCSI drafts (e.g. SPC\-3 rev 23 and SBC\-2 rev 16) increase |
| the utility of the REQUEST SENSE command. Idle and standby power |
| conditions can now be detected with this command; a progress indication |
| is given during FORMAT (when that command was started with with IMMED=1 |
| in its parameter header); and the Filemark, ILI and EOM bits may be |
| set (e.g. by a tape drive). Interestingly the sense key is set |
| to "no sense" while the asc/ascq code convey the information (e.g. |
| 0x5e/0x4 "Standby condition activated by command"). |
| .PP |
| The REQUEST SENSE command is not marked as mandatory in SPC\-3 (i.e. for |
| all SCSI devices) but is marked as mandatory in SBC\-2 (i.e. for disks), |
| SSC\-3 (i.e. for tapes) and MMC\-4 (i.e. for CD/DVD drives). |
| .SH EXIT STATUS |
| The exit status of sg_requests is 0 when it is successful. Otherwise see |
| the sg3_utils(8) man page. |
| .SH AUTHORS |
| Written by Douglas Gilbert. |
| .SH "REPORTING BUGS" |
| Report bugs to <dgilbert at interlog dot com>. |
| .SH COPYRIGHT |
| Copyright \(co 2004\-2007 Douglas Gilbert |
| .br |
| This software is distributed under a FreeBSD license. There is NO |
| warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. |
| .SH "SEE ALSO" |
| .B sg3_utils |