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Top Forums UNIX for Dummies Questions & Answers Difference between file descriptor and file pointer Post 302444882 by kvok on Friday 13th of August 2010 05:31:11 AM
Old 08-13-2010
Quote:
Originally Posted by karthigayan
File descriptor is an integer which is an index in the kernel on the opened files(Which is called file descriptor table).It is used to deal with the files . most of the functions like open,close,read using the file descriptors to deal with the files.

File pointer is a location with in the file.Which points the next character which going to read.
So shall I understand that the filedescriptor is number of amount connections for particular process/program which will be used ? and its predefined ?
 

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scsi_find_sense_descr(9F)				   Kernel Functions for Drivers 				 scsi_find_sense_descr(9F)

NAME
scsi_find_sense_descr - find descriptor in SCSI sense data SYNOPSIS
#include <sys/scsi/scsi.h> uint8_t *scsi_find_sense_descr(uint8_t *sense_buffer, int sense_buf_len, int req_descr_type); INTERFACE LEVEL
Solaris DDI specific (Solaris DDI). PARAMETERS
sense_buffer Pointer to a buffer containing SCSI descriptor sense data. The data is expected in wire format starting at the response code. sense_buf_len Integer that contains the length of sense buffer in bytes. req_descr_type Integer that contains the descriptor type value for the desired sense descriptor. DESCRIPTION
The scsi_find_sense_descr() function is used to obtain a pointer to a specific descriptor type, specified by req_descr_type, within a descriptor sense buffer. Before returning the pointer, scsi_find_sense_descr() verifies that the entire descriptor is present based on the length provided in sense_buf_len. Any value for req_descr_type can be requested. The following descriptor types are already defined: #define DESCR_INFORMATION 0x00 #define DESCR_COMMAND_SPECIFIC 0x01 #define DESCR_SENSE_KEY_SPECIFIC 0x02 #define DESCR_FRU 0x03 #define DESCR_STREAM_COMMANDS 0x04 #define DESCR_BLOCK_COMMANDS 0x05 #define DESCR_OSD_OID 0x06 #define DESCR_OSD_RESP_INTEGRITY 0x07 #define DESCR_OSD_ATTR_ID 0x08 Drivers should use scsi_validate_sense(9F) to ensure that the sense buffer contains valid descriptor sense data. RETURN VALUES
The scsi_find_sense_descr() function returns a pointer to a sense descriptor of the requested type if a descriptor of that type exists. If no such descriptor exists, scsi_find_sense_descr() returns NULL. CONTEXT
The scsi_find_sense_descr() function can be called from user or interrupt context. SEE ALSO
scsi_ext_sense_fields(9F), scsi_sense_asc(9F), scsi_sense_ascq(9F), scsi_sense_cmdspecific_uint64(9F), scsi_sense_info_uint64(9F), scsi_sense_key(9F), scsi_validate_sense(9F) SunOS 5.11 30 Jun 2006 scsi_find_sense_descr(9F)
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