10-17-2011
Deciding whether to get a buffer cache block or inode block
I was reading a book on UNIX internals "The design of the UNIX Operating system." There are two memory structures that are confusing me:
1) Buffer cache
2) Inode cache
My questions are
1) Does a process get both buffer cache and Indoe cache allocated when it opens/creates a file?
2) if no, then when does a process decide that it requires a buffer cache or/and inode cache
pls provide any pointers regarding the information on the above questions.
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LEARN ABOUT X11R4
kswitch
KSWITCH(1) General Commands Manual KSWITCH(1)
NAME
kswitch - switch primary credential cache
SYNOPSIS
kswitch {-c cachename | -p principal}
DESCRIPTION
kswitch makes the specified credential cache the primary cache for the collection, if a cache collection is available.
OPTIONS
-c cachename directly specifies the credential cache to be made primary.
-p principal causes the cache collection to be searched for a cache containing credentials for principal. If one is found, that col-
lection is made primary.
ENVIRONMENT
kswitch uses the following environment variables:
KRB5CCNAME Location of the default Kerberos 5 credentials (ticket) cache, in the form type:residual. If no type prefix is present,
the FILE type is assumed. The type of the default cache may determine the availability of a cache collection; for
instance, a default cache of type DIR causes caches within the directory to be present in the collection.
FILES
/tmp/krb5cc_[uid] default location of Kerberos 5 credentials cache ([uid] is the decimal UID of the user).
SEE ALSO
kinit(1), kdestroy(1), klist(1), kerberos(1)
KSWITCH(1)