Homepage > Man Pages > Category > Subroutines
Homepage > Man Pages > Name > A

af_find

man page of af_find

af_find: AtFS retrieve interface

NAME
af_find, af_cachefind, af_initattrs, af_getkey, af_dropkey, af_dropset, af_dropall - AtFS retrieve interface

SYNOPSIS

#include <atfs.h> int af_find (Af_attrs *attrbuf, Af_set *resultset) int af_cachefind (Af_attrs *attrbuf, Af_set *resultset) int af_initattrs (Af_attrs *attrbuf) int af_getkey (char *syspath, char *name, char *type, int gen, int rev, Af_key *aso) int af_dropkey (Af_key *key) int af_dropset (Af_set *set) int af_dropall (void)

DESCRIPTION

af_find and af_cachefind retrieve ASOs by given attributes. af_find operates on source objects and af_cachefind only on derived objects. The keys of all found ASOs are returned in resultset. The keys returned in resultset are randomly ordered. af_find and af_cachefind expect resultset to be a pointer to an empty set structure. Both functions return the number of found ASOs. The retrieve arguments are passed in an attribute buffer (attrbuf). Attrbuf should be initialized by af_initattrs before calling af_find (resp. af_cachefind). af_initattrs disables all fields in the attribute buffer. The application may then enable single fields by setting a desired attribute value. The initial settings of the single fields are listed below with the structure of the attribute buffer. Setting one of the Af_user fields in the attribute buffer to AF_NOUSER causes only ASOs to be selected, where the corresponding user attribute is not set. This makes only sense for af_locker, when the selection of ASOs that are not locked is desired. On the af_mode field, a bitwise comparison is performed. In this case, all ASOs will be selected that have at least all required mode bits (given in af_mode) set in their mode field. An exact match is not required. The first two fields in the attribute buffer denote the search space. Generally, the search space for a retrieve operation is a directory. The directory name is given in the af_syspath field in the attribute buffer. If no system path is given, the current directory is searched. The fields af_host in the attribute buffer is ignored in the current implementation. The structure of the attribute buffer is the following: typedef struct { initial value char af_host[MAXHOSTNAMELEN]; /* hostname (ignored) */"" char af_syspath[MAXPATHLEN+1]; /* system path */"" char af_name[MAXNAMLEN+1]; /* filename */"*" char af_type[MAXTYPLEN]; /* filename extension (type) */"*" int af_gen; /* generation number */-1 int af_rev; /* revision number */-1 int af_state; /* version state */ -1 Af_user af_owner; /* owner */{ "", "", "" } Af_user af_author; /* author */{ "", "", "" } off_t af_size; /* size of file */ -1 u_short af_mode; /* protection */0 Af_user af_locker; /* locker */{ "", "", "" } time_t af_mtime; /* date of last modification */-1 time_t af_atime; /* date of last access */-1 time_t af_ctime; /* date of last status change*/-1 time_t af_stime; /* save date */-1 time_t af_ltime; /* date of last lock change */-1 char *af_udattrs[AF_MAXUDAS]; /* user defined attributes */ } Af_attrs; It is possible to pass a list of user defined attributes as retrieve arguments. The list of pointers af_udattrs in the attribute buffer can be filled with strings of the form name[=value]. The list must be terminated by a nil pointer. The user defined attributes are interpreted in the following way: empty list (first entry is a nil pointer) matches every ASO. "" (first entry is an empty string) matches every ASO that has no user defined attributes. name[=] matches, if a user defined attribute with the given name is present. name=value matches all ASOs that have a corresponding user defined attribute, that has at least the given value. af_getkey builds up an object key by a combination of attributes (pathname, name, type, generation number, revision number and variant name) uniquely identifying a source ASO. Upon successful completion, the found object key is returned in the buffer key. Instead of explicit version numbers, you can pass the pseudo-numbers AF_BUSYVERS, AF_FIRSTVERS or AF_LASTVERS to af_getkey. af_getkey works only on source objects. The call af_getkey ("", "otto", "c", AF_BUSYVERS, AF_BUSYVERS, key) leads to the key of the file (busy version) named otto.c in the current directory. af_getkey ("", "otto", "c", AF_LASTVERS, AF_LASTVERS, key) delivers the last saved version (if present) of the history of otto.c. After having retrieved a key or a set of keys, the data for the corresponding object version(s) remains cached in memory as long as the application does not explicitly give the key back. The function af_dropkey gives a key back and releases the object version. A retrieved set of keys has to be given back by use of af_dropset. af_dropall sets all reference counters for cached object versions to zero, that means, it gives all formerly retrieved keys and sets back.

DIAGNOSTICS

af_find returns the number of found ASOs. Upon error, -1 is returned and af_errno is set to the corresponding error number. AF_FIND(3)
 
 
 

Copyright © 2011–2018 by topics-of-interest.com . All rights reserved. Hosted by all-inkl.
Contact · Imprint · Privacy

Page generated in 26.89ms.

meinehunde.net | schuhefinden.de | www.daelim-forum.com