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statuses.</font></p>
</div>
<hr>
<div style="margin-left: 10em">
<pre>
<b><font color="#0000FF">Timestamp Currency Functions</font>
Record  Owner  Member  Set  X_exit</b>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-18. Timestamp Currency
Functions Submenu</b></font></p>
<div style="margin-left: 4em">
<p>Record<br>
Issues a message indicating the timestamp status of the current
record.</p>
<p>Owner<br>
Issues a message indicating the timestamp status of the current
owner. Select the set whose owner's timestamp is to be checked from
the displayed selection list.</p>
<p>Member<br>
Issues a message indicating the timestamp status of the current
member. Select the set whose member's timestamp is to be checked
from the displayed selection list.</p>
<p>Set<br>
Issues a message indicating the timestamp status of a set. Select
the set whose timestamp is to be checked from the displayed
selection list.</p>
</div>
<h3>8.4.4 Using the Access Transaction Commands</h3>
<p><font size="2">The <b>Transaction</b> command, selected from the
<b>Database Access Commands</b> submenu, controls the initiation
and termination of transactions. It invokes the <b>Transaction</b>
<b>Processing Functions</b> submenu, shown below, from which a
transaction can be started (<b>Begin</b>), ended (<b>End</b>), or
aborted (<b>Abort</b>).</font></p>
<hr>
<div style="margin-left: 8em">
<pre>
<font color="#0000FF">Transaction Processing Functions
Begin</font><font color="#0000FF" size="1"> </font><font color=
"#0000FF"> End  Abort  X_exit</font>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-19. Transaction
Processing Functions Submenu</b></font></p>
<h4>Begin command</h4>
<div style="margin-left: 2em">
<p><font size="2">Starts a transaction. You are prompted to enter
the transaction identifier.</font></p>
</div>
<h4>End command</h4>
<div style="margin-left: 2em">
<p><font size="2">Stops a transaction. It applies to the database
files all changes made since the beginning of the
transaction.</font></p>
</div>
<h4>Abort command</h4>
<div style="margin-left: 2em">
<p><font size="2">Aborts the current transaction. It discards all
changes made since the beginning of the transaction.</font></p>
</div>
<h3>8.4.5 Using the Access Lock Commands</h3>
<p><font size="2">The <b>Lock</b> command, selected from the
<b>Database Access Commands</b> submenu, is used to lock set types,
record types, and key types, as well as the current record. It
invokes the <b>Multiuser Set/Record Lock Functions</b> submenu,
shown in Fig. 8-20, from which you select either record, set, key,
or current locks. You then select the record, set, or key to be
locked from the displayed list of record, set, or key names defined
in the database.</font></p>
<hr>
<div style="margin-left: 8em">
<pre>
<b><font color="#0000FF">Multiuser Set/Record Lock Functions</font>
Record  Set  Key  Current  Display  X_exit</b>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-20. Timestamp Currency
Functions Submenu</b></font></p>
<h4>Record command</h4>
<div style="margin-left: 2em">
<p><font size="2">Places a lock on the record type selected from
the displayed list of records. A selection list of lock types will
be displayed, from which you should select the desired lock type.
This command can only be executed when the database is opened for
shared access.</font></p>
</div>
<h4>Set command</h4>
<div style="margin-left: 2em">
<p><font size="2">Places a lock on the set type selected from the
displayed list of sets. A selection list of lock types will be
displayed, from which you should select the desired lock type. This
command can only be executed when the database is opened for shared
access.</font></p>
</div>
<h4>Key command</h4>
<div style="margin-left: 2em">
<p><font size="2">Places a lock on the key type selected from the
displayed list of keys. A selection list of lock types will be
displayed, from which you should select the desired lock type. This
command can only be executed when the database is opened for shared
access.</font></p>
</div>
<h4>Current command</h4>
<div style="margin-left: 2em">
<p><font size="2">Sets the record lock bit of the current
record.</font></p>
</div>
<h4>Display command</h4>
<div style="margin-left: 2em">
<p><font size="2">Displays the lock status for each set, record,
and key type, indicating whether it is read-locked, read-locked
with keep, write-locked, exclusively locked, or free. This command
can only be executed when the database is opened for shared
access.</font></p>
</div>
<h3>8.4.6 Using the Access Free Commands</h3>
<p><font size="2">The <b>Free</b> command, selected from the
<b>Database Access Commands</b> submenu, is used to free locked
record, set, and key types, or to clear the current record's lock
bit. <b>Free</b> invokes the <b>Multi-user Set/Record Free Locks
Functions</b> submenu, shown in Figure 8-21. From here you select
which locks you want freed. If you are freeing a set, record, or
key lock, select the correct one from the displayed list of names
defined in the database.</font></p>
<hr>
<div style="margin-left: 8em">
<pre>
<font color="#0000FF">Multi-user Set/Record Free Locks Functions
Record  Set  Key  All  Current  X_exit</font>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-21. Multi-user
Set/Record Free Locks Functions Submenu</b></font></p>
<h4>Record command</h4>
<div style="margin-left: 2em">
<p><font size="2">Frees the lock for the record type selected from
the displayed list of record types. This command can only be
executed when the database is opened for shared access and when no
transaction is active.</font></p>
</div>
<h4>Set command</h4>
<div style="margin-left: 2em">
<p><font size="2">Frees the lock for the set type selected from the
displayed list of set types. This command can only be executed when
the database is opened for shared access and when no transaction is
active.</font></p>
</div>
<h4>Key command</h4>
<div style="margin-left: 2em">
<p><font size="2">Frees the lock for the key type selected from the
displayed list of key types. This command can only be executed when
the database is opened for shared access and when no transaction is
active.</font></p>
</div>
<h4>All command</h4>
<div style="margin-left: 2em">
<p><font size="2">Frees all set, record and key locks. It can only
be executed when the database is opened for shared access and when
no transaction is active.</font></p>
</div>
<h4>Current command</h4>
<div style="margin-left: 2em">
<p><font size="2">Clears the lock bit of the current
record.</font></p>
</div>
<h3>8.4.7 Using the Access Misc Commands</h3>
<p><font size="2">The <b>Misc</b> command, selected from the
<b>Database Access Commands</b> submenu, invokes the
<b>Miscellaneous ida Functions</b> submenu, shown in Figure 8-22,
for displaying current database file and lock statuses.</font></p>
<hr>
<div style="margin-left: 12em">
<pre>
<font color="#0000FF">Miscellaneous ida Functions
Files  Locks  X_exit</font>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-22. Miscellaneous ida
Functions Submenu</b></font></p>
<h4>Files command</h4>
<div style="margin-left: 2em">
<p><font size="2">Displays status information pertaining to the
database and all database files, as shown in Table 8-4.</font></p>
</div>
<h4>Locks command</h4>
<div style="margin-left: 2em">
<p><font size="2">Displays the lock status for each set, record,
and key type, indicating whether it is read-locked, read-locked
with keep, write-locked, exclusively locked, or free. This command
can only be executed when the database is opened for shared
access.</font></p>
</div>
<p align="center"><b>Table 8-4. File Status Information (From the
Misc Files Command)</b></p>
<table border="1" cellpadding="7" cellspacing="1" width="542">
<tr>
<td valign="top" width="23%">
<p><b><font size="2">Item Name</font></b></p>
</td>
<td valign="top" width="77%">
<p><b><font size="2">Description</font></b></p>
</td>
</tr>
<tr>
<td valign="top" width="23%">
<p><font size="2">Database name</font></p>
</td>
<td valign="top" width="77%">
<p><font size="2">The name of the database currently being
accessed.</font></p>
</td>
</tr>
<tr>
<td valign="top" width="23%">
<p><font size="2">Access type</font></p>
</td>
<td valign="top" width="77%">
<p><font size="2">Exclusive, shared, or one_user access.</font></p>
</td>
</tr>
<tr>
<td valign="top" width="23%">
<p><font size="2">Transaction</font></p>
</td>
<td valign="top" width="77%">
<p><font size="2">The identifier of the active
transaction.</font></p>
</td>
</tr>
<tr>
<td valign="top" width="23%">
<p><font size="2">FILE</font></p>
</td>
<td valign="top" width="77%">
<p><font size="2">The file number of the listed file.</font></p>
</td>
</tr>
<tr>
<td valign="top" width="23%">
<p><font size="2">SLOTS</font></p>
</td>
<td valign="top" width="77%">
<p><font size="2">The total number of allocated file slots (if data
file) or pages (if key file).</font></p>
</td>
</tr>
<tr>
<td valign="top" width="23%">
<p><font size="2">TYPE</font></p>
</td>
<td valign="top" width="77%">
<p><font size="2">The file type: either "<b>data</b>" or
"<b>key</b>".</font></p>
</td>
</tr>
<tr>
<td valign="top" width="23%">
<p><font size="2">STATUS</font></p>
</td>
<td valign="top" width="77%">
<p><font size="2">File status: "<b>opened</b>" or "<b>closed</b>",
"<b>locked</b>" or "<b>free.</b>"</font></p>
</td>
</tr>
<tr>
<td valign="top" width="23%">
<p><font size="2">RW</font></p>
</td>
<td valign="top" width="77%">
<p><font size="2">The total number of read locks on the file within
this application. A file may be locked from different set/record
locks. This value gives the current total. It is displayed only
when the database is opened for shared access. A value of -1
indicates that the file is write-locked.</font></p>
</td>
</tr>
<tr>
<td valign="top" width="23%">
<p><font size="2">EX</font></p>
</td>
<td valign="top" width="77%">
<p><font size="2">The total number of exclusive locks on the file.
A file may be exclusively locked from different set/record locks.
This value gives the current total. It is displayed only when the
database is opened for shared access.</font></p>
</td>
</tr>
<tr>
<td valign="top" width="23%">
<p><font size="2">NAME</font></p>
</td>
<td valign="top" width="77%">
<p><font size="2">The name of the file including any current path
names.</font></p>
</td>
</tr>
</table>
<p><font size="2">&nbsp;</font></p>
<h2><a name="CrossReferenced" id="CrossReferenced"></a>8.5
<i>db.*</i> Functions Cross-Referenced to ida Commands</h2>
<p><font size="2">The <b>ida</b> utility allows you to use a
menu-driven interface instead of entering <b><i>db.*</i></b>
functions from the command line. Table 8-5 lists <b><i>db.*</i></b>
functions and the corresponding sequence of <b>ida</b> menu
commands that produce the same result. This list is helpful when
learning how to use the various <b><i>db.*</i></b> functions. For
complete information on the operation of a particular
<b><i>db.*</i></b> C function, refer to the detailed function
descriptions in the <b><i>db.*</i> Reference Manual</b>.</font></p>
<p>In the following list, functions are grouped by type of
operation. The function name is in the left column, and the
<b>ida</b> menu command sequence is in the right column.</p>
<p align="center"><b>Table 8-5. <i>db.*</i> Functions and
Corresponding ida Command Sequences</b></p>
<p>Database Administration Functions</p>
<table border="1" cellpadding="7" cellspacing="1" width="542">
<tr>
<td valign="top" width="25%">
<p><b><font size="2">Function</font></b></p>
</td>
<td valign="top" width="75%">
<p><b><font size="2">ida Menu Command Sequence</font></b></p>
</td>
</tr>
<tr>
<td valign="top" width="25%">
<p><b><font size="2">d_setpages</font></b></p>
</td>
<td valign="top" width="75%">
<p><font size="2">Parameters Pages</font></p>
</td>
</tr>
<tr>
<td valign="top" width="25%">
<p><b><font size="2">d_setfiles</font></b></p>
</td>
<td valign="top" width="75%">
<p><font size="2">Parameters Max_files</font></p>
</td>
</tr>
<tr>
<td valign="top" width="25%">
<p><b><font size="2">d_dbdpath</font></b></p>
</td>
<td valign="top" width="75%">
<p><font size="2">Parameters Dictionary_path</font></p>
</td>
</tr>
<tr>
<td valign="top" width="25%">
<p><b><font size="2">d_dbfpath</font></b></p>
</td>
<td valign="top" width="75%">
<p><font size="2">Parameters Files_path</font></p>
</td>
</tr>
<tr>
<td valign="top" width="25%">
<p><b><font size="2">d_dbuserid</font></b></p>
</td>
<td valign="top" width="75%">
<p><font size="2">Parameters Userid</font></p>
</td>