1Ace::Local(3)         User Contributed Perl Documentation        Ace::Local(3)
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NAME

6       Ace::Local - use giface, tace or gifaceclient to open a local connec‐
7       tion to an Ace database
8

SYNOPSIS

10         use Ace::Local
11         my $ace = Ace::Local->connect(-path=>'/usr/local/acedb/elegans');
12         $ace->query('find author Se*');
13         die "Query unsuccessful" unless $ace->status;
14         $ace->query('show');
15         while ($ace->encore) {
16           print $ace->read;
17         }
18

DESCRIPTION

20       This class is provided for low-level access to local (non-networked)
21       Ace databases via the giface program.  You will generally not need to
22       access it directly.  Use Ace.pm instead.
23
24       For the sake of completeness, the method can also use the aceclient
25       program for its access.  However the Ace::AceDB class is more efficient
26       for this purpose.
27

METHODS

29       connect()
30
31         $accessor = Ace::Local->connect(-path=>$path_to_database);
32
33       Connect to the database at the indicated path using giface and return a
34       connection object (an "accessor").  Giface must be on the current
35       search path.  Multiple accessors may be open simultaneously.
36
37       Arguments include:
38
39       -path
40           Path to the database (location of the "wspec/" directory).
41
42       -program
43           Used to indicate the location of the desired giface or gifaceclient
44           executable.  You may also use tace or aceclient, but in that case
45           the asGIF() functionality will nog work.  Can be used to override
46           the search path.
47
48       -host
49           Used when invoking gifaceclient.  Indicates the host to connect to.
50
51       -port
52           Used when invoking gifaceclient.  Indicates the port to connect to.
53
54       -nosync
55           Ordinarily Ace::Local synchronizes with the tace/giface prompt,
56           throwing out all warnings and copyright messages.  If this is set,
57           Ace::Local will not do so.  In this case you must call the
58           low_read() method until it returns undef in order to synchronize.
59
60       query()
61
62         $status = $accessor->query('query string');
63
64       Send the query string to the server and return a true value if success‐
65       ful.  You must then call read() repeatedly in order to fetch the query
66       result.
67
68       read()
69
70       Read the result from the last query sent to the server and return it as
71       a string.  ACE may return the result in pieces, breaking between whole
72       objects.  You may need to read repeatedly in order to fetch the entire
73       result.  Canonical example:
74
75         $accessor->query("find Sequence D*");
76         die "Got an error ",$accessor->error() if $accessor->status == STATUS_ERROR;
77         while ($accessor->status == STATUS_PENDING) {
78            $result .= $accessor->read;
79         }
80
81       low_read()
82
83       Read whatever data's available, or undef if none.  This is only used by
84       the ace.pl replacement for giface/tace.
85
86       status()
87
88       Return the status code from the last operation.  Status codes are
89       exported by default when you use Ace.pm.  The status codes you may see
90       are:
91
92         STATUS_WAITING    The server is waiting for a query.
93         STATUS_PENDING    A query has been sent and Ace is waiting for
94                           you to read() the result.
95         STATUS_ERROR      A communications or syntax error has occurred
96
97       error()
98
99       May return a more detailed error code supplied by Ace.  Error checking
100       is not fully implemented.
101
102       encore()
103
104       This method will return true after you have performed one or more
105       read() operations, and indicates that there is more data to read.
106       encore() is functionally equivalent to:
107
108          $encore = $accessor->status == STATUS_PENDING;
109
110       In fact, this is how it's implemented.
111
112       auto_save()
113
114       Sets or queries the auto_save variable.  If true, the "save" command
115       will be issued automatically before the connection to the database is
116       severed.  The default is true.
117
118       Examples:
119
120          $accessor->auto_save(1);
121          $flag = $accessor->auto_save;
122

SEE ALSO

124       Ace, Ace::Object, Ace::Iterator, Ace::Model
125

AUTHOR

127       Lincoln Stein <lstein@w3.org> with extensive help from Jean Thierry-
128       Mieg <mieg@kaa.crbm.cnrs-mop.fr>
129
130       Copyright (c) 1997-1998, Lincoln D. Stein
131
132       This library is free software; you can redistribute it and/or modify it
133       under the same terms as Perl itself.  See DISCLAIMER.txt for dis‐
134       claimers of warranty.
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138perl v5.8.8                       2001-02-20                     Ace::Local(3)