What action updates a file's ACCESS time?
Boyd Roberts
boyd at necisa.ho.necisa.oz
Mon Dec 10 14:05:28 AEST 1990
In article <893 at jonlab.UUCP> jon at jonlab.UUCP (Jon H. LaBadie) writes:
>In article <331 at twg.bc.ca> bill at twg.bc.ca (Bill Irwin) writes:
>>I would like to know ALL the possible activities that could result in a file's
>>access time (ls -lu) being updated.
>
Reading the data in the file update its access time.
>Note also that write's to a file require a read first. You may want to
>write one character. But disks transfer data in blocks. Thus, to
>write your one character, the block it will be written in must be read
>into memory. You will "write" your one character into that memory
>buffer and the entire block will be written to disk.
>
>Thus writes also update access times.
>
No, that read is not always neccessary. If the write spans the block no read
is neccessary. Should a read be necessary, the read happens invisibly in that
the access time is not changed. That read is not a true access of the file.
It's a side affect of the file-system implementation.
Boyd Roberts boyd at necisa.ho.necisa.oz.au
``When the going gets wierd, the weird turn pro...''
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