Elektra  0.8.12
Public Member Functions
kdb::KeySet Class Reference

A keyset holds together a set of keys. More...

#include <keyset.hpp>

Public Member Functions

 KeySet ()
 Creates a new empty keyset with no keys.
 KeySet (ckdb::KeySet *k)
 Takes ownership of keyset!
 KeySet (const KeySet &other)
 Duplicate a keyset.
 KeySet (size_t alloc,...)
 Create a new keyset.
 KeySet (Va va, size_t alloc, va_list ap)
 Create a new keyset.
 ~KeySet ()
 Deconstruct a keyset.
ckdb::KeySet * release ()
 If you don't want destruction of keyset at the end you can release the pointer.
ckdb::KeySet * getKeySet () const
 Passes out the raw keyset pointer.
void setKeySet (ckdb::KeySet *k)
 Take ownership of passed keyset.
KeySetoperator= (KeySet const &other)
 Duplicate a keyset.
ssize_t size () const
 The size of the keyset.
ckdb::KeySet * dup () const
 Duplicate a keyset.
void copy (const KeySet &other)
 Copy a keyset.
void clear ()
 Clear the keyset.
ssize_t append (const Key &toAppend)
 append a key
ssize_t append (const KeySet &toAppend)
 append a keyset
Key head () const
Key tail () const
void rewind () const
Key next () const
Key current () const
void setCursor (cursor_t cursor) const
cursor_t getCursor () const
Key pop ()
KeySet cut (Key k)
Key lookup (const Key &k, const option_t options=KDB_O_NONE) const
Key lookup (std::string const &name, const option_t options=KDB_O_NONE) const
 Lookup a key by name.
Key at (cursor_t pos) const
 Lookup a key by index.

Detailed Description

A keyset holds together a set of keys.

Methods to manipulate KeySets.

A KeySet is a set of keys.

Most important properties of a KeySet:

The most important methods of KeySet:

Note:
Because the key is not copied, also the pointer to the current metadata keyNextMeta() will be shared.

With ksRewind() and ksNext() you can iterate through the keyset. Be assured that you will get every key of the set in a stable order (parents before children).

KeySets have an internal cursor . Methods should avoid to change this cursor, unless they want to communicate something with it. The internal cursor is used:

KeySet is the most important data structure in Elektra. It makes it possible to get and store many keys at once inside the database. In addition to that, the class can be used as high level datastructure in applications and it can be used in plugins to manipulate or check configuration.

With ksLookupByName() it is possible to fetch easily specific keys out of the list of keys.

You can easily create and iterate keys:

#include <kdb.h>

// create a new keyset with 3 keys
// with a hint that about 20 keys will be inside
KeySet *myConfig = ksNew(20,
        keyNew ("user/name1", 0),
        keyNew ("user/name2", 0),
        keyNew ("user/name3", 0),
        KS_END);
// append a key in the keyset
ksAppendKey(myConfig, keyNew("user/name4", 0));

Key *current;
ksRewind(myConfig);
while ((current=ksNext(myConfig))!=0)
{
        printf("Key name is %s.\n", keyName (current));
}
ksDel (myConfig); // delete keyset and all keys appended
Invariant:
always holds an underlying elektra keyset.
Note:
that the cursor is mutable, so it might be changed even in const functions as described.

Constructor & Destructor Documentation

kdb::KeySet::KeySet ( ) [inline]

Creates a new empty keyset with no keys.

Allocate, initialize and return a new KeySet object.

Objects created with ksNew() must be destroyed with ksDel().

You can use a various long list of parameters to preload the keyset with a list of keys. Either your first and only parameter is 0 or your last parameter must be KEY_END.

So, terminate with ksNew(0, KS_END) or ksNew(20, ..., KS_END)

For most uses

KeySet *keys = ksNew(0, KS_END);
// work with it
ksDel (keys);

goes ok, the alloc size will be 16, defined in kdbprivate.h. The alloc size will be doubled whenever size reaches alloc size, so it also performs out large keysets.

But if you have any clue how large your keyset may be you should read the next statements.

If you want a keyset with length 15 (because you know of your application that you normally need about 12 up to 15 keys), use:

KeySet * keys = ksNew (15,
        keyNew ("user/sw/app/fixedConfiguration/key01", KEY_SWITCH_VALUE, "value01", 0),
        keyNew ("user/sw/app/fixedConfiguration/key02", KEY_SWITCH_VALUE, "value02", 0),
        keyNew ("user/sw/app/fixedConfiguration/key03", KEY_SWITCH_VALUE, "value03", 0),
        // ...
        keyNew ("user/sw/app/fixedConfiguration/key15", KEY_SWITCH_VALUE, "value15", 0),
        KS_END);
// work with it
ksDel (keys);

If you start having 3 keys, and your application needs approximately 200-500 keys, you can use:

KeySet * config = ksNew (500,
        keyNew ("user/sw/app/fixedConfiguration/key1", KEY_SWITCH_VALUE, "value1", 0),
        keyNew ("user/sw/app/fixedConfiguration/key2", KEY_SWITCH_VALUE, "value2", 0),
        keyNew ("user/sw/app/fixedConfiguration/key3", KEY_SWITCH_VALUE, "value3", 0),
        KS_END); // don't forget the KS_END at the end!
// work with it
ksDel (config);

Alloc size is 500, the size of the keyset will be 3 after ksNew. This means the keyset will reallocate when appending more than 497 keys.

The main benefit of taking a list of variant length parameters is to be able to have one C-Statement for any possible KeySet.

Postcondition:
the keyset is rewinded properly
See also:
ksDel() to free the KeySet afterwards
ksDup() to duplicate an existing KeySet
Parameters:
allocgives a hint for the size how many Keys may be stored initially
Returns:
a ready to use KeySet object
0 on memory error
kdb::KeySet::KeySet ( ckdb::KeySet *  k) [inline]

Takes ownership of keyset!

Keyset will be destroyed at destructor you cant continue to use keyset afterwards!

Use KeySet::release() to avoid destruction.

Parameters:
kthe keyset to take the ownership from
See also:
release()
setKeySet()
kdb::KeySet::KeySet ( const KeySet other) [inline]

Duplicate a keyset.

This keyset will be a duplicate of the other afterwards.

Note:
that they still reference to the same Keys, so if you change key values also the keys in the original keyset will be changed.

So it is shallow copy, to create a deep copy you have to dup() every key (it still won't copy meta data, but they are COW):

kdb::KeySet ksDeepCopy(kdb::KeySet orig)
{
        kdb::KeySet deepCopy;
        orig.rewind();
        while(orig.next())
        {
                deepCopy.append(orig.current().dup());
        }
        return deepCopy;
}
See also:
dup
kdb::KeySet::KeySet ( size_t  alloc,
  ... 
) [inline, explicit]

Create a new keyset.

Parameters:
allocminimum number of keys to allocate
...variable argument list

Allocate, initialize and return a new KeySet object.

Objects created with ksNew() must be destroyed with ksDel().

You can use a various long list of parameters to preload the keyset with a list of keys. Either your first and only parameter is 0 or your last parameter must be KEY_END.

So, terminate with ksNew(0, KS_END) or ksNew(20, ..., KS_END)

For most uses

KeySet *keys = ksNew(0, KS_END);
// work with it
ksDel (keys);

goes ok, the alloc size will be 16, defined in kdbprivate.h. The alloc size will be doubled whenever size reaches alloc size, so it also performs out large keysets.

But if you have any clue how large your keyset may be you should read the next statements.

If you want a keyset with length 15 (because you know of your application that you normally need about 12 up to 15 keys), use:

KeySet * keys = ksNew (15,
        keyNew ("user/sw/app/fixedConfiguration/key01", KEY_SWITCH_VALUE, "value01", 0),
        keyNew ("user/sw/app/fixedConfiguration/key02", KEY_SWITCH_VALUE, "value02", 0),
        keyNew ("user/sw/app/fixedConfiguration/key03", KEY_SWITCH_VALUE, "value03", 0),
        // ...
        keyNew ("user/sw/app/fixedConfiguration/key15", KEY_SWITCH_VALUE, "value15", 0),
        KS_END);
// work with it
ksDel (keys);

If you start having 3 keys, and your application needs approximately 200-500 keys, you can use:

KeySet * config = ksNew (500,
        keyNew ("user/sw/app/fixedConfiguration/key1", KEY_SWITCH_VALUE, "value1", 0),
        keyNew ("user/sw/app/fixedConfiguration/key2", KEY_SWITCH_VALUE, "value2", 0),
        keyNew ("user/sw/app/fixedConfiguration/key3", KEY_SWITCH_VALUE, "value3", 0),
        KS_END); // don't forget the KS_END at the end!
// work with it
ksDel (config);

Alloc size is 500, the size of the keyset will be 3 after ksNew. This means the keyset will reallocate when appending more than 497 keys.

The main benefit of taking a list of variant length parameters is to be able to have one C-Statement for any possible KeySet.

Postcondition:
the keyset is rewinded properly
See also:
ksDel() to free the KeySet afterwards
ksDup() to duplicate an existing KeySet
Parameters:
allocgives a hint for the size how many Keys may be stored initially
Returns:
a ready to use KeySet object
0 on memory error
Precondition:
caller must call va_start and va_end
va the list of arguments
Parameters:
allocthe allocation size
vathe list of variable arguments
kdb::KeySet::KeySet ( Va  va,
size_t  alloc,
va_list  av 
) [inline, explicit]

Create a new keyset.

Parameters:
allocminimum number of keys to allocate
apvariable arguments list

Use va as first argument to use this constructor, e.g.:

 KeySet ks(va, 23, ...);

Allocate, initialize and return a new KeySet object.

Objects created with ksNew() must be destroyed with ksDel().

You can use a various long list of parameters to preload the keyset with a list of keys. Either your first and only parameter is 0 or your last parameter must be KEY_END.

So, terminate with ksNew(0, KS_END) or ksNew(20, ..., KS_END)

For most uses

KeySet *keys = ksNew(0, KS_END);
// work with it
ksDel (keys);

goes ok, the alloc size will be 16, defined in kdbprivate.h. The alloc size will be doubled whenever size reaches alloc size, so it also performs out large keysets.

But if you have any clue how large your keyset may be you should read the next statements.

If you want a keyset with length 15 (because you know of your application that you normally need about 12 up to 15 keys), use:

KeySet * keys = ksNew (15,
        keyNew ("user/sw/app/fixedConfiguration/key01", KEY_SWITCH_VALUE, "value01", 0),
        keyNew ("user/sw/app/fixedConfiguration/key02", KEY_SWITCH_VALUE, "value02", 0),
        keyNew ("user/sw/app/fixedConfiguration/key03", KEY_SWITCH_VALUE, "value03", 0),
        // ...
        keyNew ("user/sw/app/fixedConfiguration/key15", KEY_SWITCH_VALUE, "value15", 0),
        KS_END);
// work with it
ksDel (keys);

If you start having 3 keys, and your application needs approximately 200-500 keys, you can use:

KeySet * config = ksNew (500,
        keyNew ("user/sw/app/fixedConfiguration/key1", KEY_SWITCH_VALUE, "value1", 0),
        keyNew ("user/sw/app/fixedConfiguration/key2", KEY_SWITCH_VALUE, "value2", 0),
        keyNew ("user/sw/app/fixedConfiguration/key3", KEY_SWITCH_VALUE, "value3", 0),
        KS_END); // don't forget the KS_END at the end!
// work with it
ksDel (config);

Alloc size is 500, the size of the keyset will be 3 after ksNew. This means the keyset will reallocate when appending more than 497 keys.

The main benefit of taking a list of variant length parameters is to be able to have one C-Statement for any possible KeySet.

Postcondition:
the keyset is rewinded properly
See also:
ksDel() to free the KeySet afterwards
ksDup() to duplicate an existing KeySet
Parameters:
allocgives a hint for the size how many Keys may be stored initially
Returns:
a ready to use KeySet object
0 on memory error
Precondition:
caller must call va_start and va_end
va the list of arguments
Parameters:
allocthe allocation size
vathe list of variable arguments
kdb::KeySet::~KeySet ( ) [inline]

Deconstruct a keyset.

A destructor for KeySet objects.

Cleans all internal dynamic attributes, decrement all reference pointers to all keys and then keyDel() all contained Keys, and free()s the release the KeySet object memory (that was previously allocated by ksNew()).

Parameters:
ksthe keyset object to work with
Returns:
0 when the keyset was freed
-1 on null pointer
See also:
ksNew()

Member Function Documentation

ssize_t kdb::KeySet::append ( const Key toAppend) [inline]

append a key

Parameters:
toAppendkey to append
Returns:
number of keys in the keyset

Appends a Key to the end of ks.

Will take ownership of the key toAppend. That means ksDel(ks) will remove the key unless the key:

  • was duplicated before inserting
  • got its refcount incremented by keyIncRef() before inserting
  • was also inserted into another keyset with ksAppendKey()

The reference counter of the key will be incremented to show this ownership, and thus toAppend is not const.

Note:
Because the key is not copied, also the pointer to the current metadata keyNextMeta() will be shared.
See also:
keyGetRef().

If the keyname already existed in the keyset, it will be replaced with the new key.

The KeySet internal cursor will be set to the new key.

It is save to directly append newly created keys:

KeySet *ks = ksNew(1, KS_END);
ksAppendKey(ks,
        keyNew("user/my/new/key", KEY_END));
ksDel(ks);
// key deleted, too!

If you want the key to outlive the keyset, make sure to do proper ref counting:

KeySet *ks = ksNew(1, KS_END);
Key *k = keyNew("user/ref/key", KEY_END);
keyIncRef(k);
ksAppendKey(ks, k);
ksDel(ks);
// now we still can work with the key k!
keyDecRef(k);
keyDel(k);

Or if you want to avoid aliasing at all, you can duplicate the key. But then key in the keyset has another identity:

KeySet *ks = ksNew(1, KS_END);
Key *k = keyNew("user/ref/key", KEY_END);
ksAppendKey(ks, keyDup(k));
ksDel(ks);
// now we still can work with the key k!
keyDel(k);
Returns:
the size of the KeySet after insertion
-1 on NULL pointers
-1 if insertion failed, the key will be deleted then.
Parameters:
ksKeySet that will receive the key
toAppendKey that will be appended to ks or deleted
See also:
ksAppend(), keyNew(), ksDel()
keyIncRef()
ssize_t kdb::KeySet::append ( const KeySet toAppend) [inline]

append a keyset

Parameters:
toAppendkeyset to append
Returns:
number of keys in the keyset

Append all toAppend contained keys to the end of the ks.

toAppend KeySet will be left unchanged.

If a key is both in toAppend and ks, the Key in ks will be overridden.

Note:
Because the key is not copied, also the pointer to the current metadata keyNextMeta() will be shared.
Postcondition:
Sorted KeySet ks with all keys it had before and additionally the keys from toAppend
Returns:
the size of the KeySet after transfer
-1 on NULL pointers
Parameters:
ksthe KeySet that will receive the keys
toAppendthe KeySet that provides the keys that will be transferred
See also:
ksAppendKey()
Key kdb::KeySet::at ( cursor_t  pos) const [inline]

Lookup a key by index.

Parameters:
poscursor position
Returns:
the found key
void kdb::KeySet::clear ( ) [inline]

Clear the keyset.

Keyset will have no keys afterwards.

void kdb::KeySet::copy ( const KeySet other) [inline]

Copy a keyset.

Parameters:
otherother keyset to copy

This is only a shallow copy. For a deep copy you need to dup every key.

Copy a keyset.

Most often you may want a duplicate of a keyset, see ksDup() or append keys, see ksAppend(). But in some situations you need to copy a keyset to a existing keyset, for that this function exists.

You can also use it to clear a keyset when you pass a NULL pointer as source.

Note that all keys in dest will be deleted. Afterwards the content of the source will be added to the destination and the ksCurrent() is set properly in dest.

A flat copy is made, so the keys will not be duplicated, but there reference counter is updated, so both keysets need to be ksDel().

Note:
Because the key is not copied, also the pointer to the current metadata keyNextMeta() will be shared.
int f (KeySet *ks)
{
        KeySet *c = ksNew (20, ..., KS_END);
        // c receives keys
        ksCopy (ks, c); // pass the keyset to the caller

        ksDel (c);
}       // caller needs to ksDel (ks)
Parameters:
sourcehas to be an initialized source KeySet or NULL
desthas to be an initialized KeySet where to write the keys
Returns:
1 on success
0 if dest was cleared successfully (source is NULL)
-1 on NULL pointer
See also:
ksNew(), ksDel(), ksDup()
keyCopy() for copying keys
Key kdb::KeySet::current ( ) const [inline]

Return the current Key.

The pointer is NULL if you reached the end or after ksRewind().

Note:
You must not delete the key or change the key, use ksPop() if you want to delete it.
Parameters:
ksthe keyset object to work with
Returns:
pointer to the Key pointed by ks's cursor
0 on NULL pointer
See also:
ksNext(), ksRewind()
KeySet kdb::KeySet::cut ( Key  k) [inline]

Cuts out a keyset at the cutpoint.

Searches for the cutpoint inside the KeySet ks. If found it cuts out everything which is below (see keyIsBelow()) this key. These keys will be missing in the keyset ks. Instead, they will be moved to the returned keyset. If cutpoint is not found an empty keyset is returned and ks is not changed.

The cursor will stay at the same key as it was before. If the cursor was inside the region of cut (moved) keys, the cursor will be set to the key before the cutpoint.

If you use ksCut() on a keyset you got from kdbGet() and plan to make a kdbSet() later, make sure that you keep all keys that should not be removed permanently. You have to keep the KeySet that was returned and the KeySet ks.

Example:

You have the keyset ks:

  • system/mountpoint/interest
  • system/mountpoint/interest/folder
  • system/mountpoint/interest/folder/key1
  • system/mountpoint/interest/folder/key2
  • system/mountpoint/other/key1

When you use

        Key *parentKey = keyNew("system/mountpoint/interest", KEY_END);
        KDB *kdb = kdbOpen(parentKey);
        KeySet *ks = ksNew(0, KS_END);
        kdbGet(kdb, ks, parentKey);
        KeySet *returned = ksCut(ks, parentKey);
        kdbSet(kdb, ks, parentKey); // all keys below cutpoint are now removed
        kdbClose(kdb, parentKey);

Then in returned are:

  • system/mountpoint/interest
  • system/mountpoint/interest/folder
  • system/mountpoint/interest/folder/key1
  • system/mountpoint/interest/folder/key2

And in ks are:

  • system/mountpoint/other/key1

So kdbSet() permanently removes all keys below system/mountpoint/interest.

See also:
kdbGet() for explanation why you might get more keys than you requested.
Returns:
a new allocated KeySet which needs to deleted with ksDel(). The keyset consists of all keys (of the original keyset ks) below the cutpoint. If the key cutpoint exists, it will also be appended.
Return values:
0on null pointers, no key name or allocation problems
Parameters:
ksthe keyset to cut. It will be modified by removing all keys below the cutpoint. The cutpoint itself will also be removed.
cutpointthe point where to cut out the keyset
ckdb::KeySet * kdb::KeySet::dup ( ) const [inline]

Duplicate a keyset.

Returns:
a copy of the keys

This is only a shallow copy. For a deep copy you need to dup every key.

Return a duplicate of a keyset.

Objects created with ksDup() must be destroyed with ksDel().

Memory will be allocated as needed for dynamic properties, so you need to ksDel() the returned pointer.

A flat copy is made, so the keys will not be duplicated, but there reference counter is updated, so both keysets need ksDel().

Parameters:
sourcehas to be an initialized source KeySet
Returns:
a flat copy of source on success
0 on NULL pointer
See also:
ksNew(), ksDel()
keyDup() for Key duplication
cursor_t kdb::KeySet::getCursor ( ) const [inline]

Get the KeySet internal cursor.

Use it to get the cursor of the actual position.

Warning:
Cursors are getting invalid when the key was ksPop()ed or ksLookup() with KDB_O_POP was used.
ckdb::KeySet * kdb::KeySet::getKeySet ( ) const [inline]

Passes out the raw keyset pointer.

Returns:
pointer to internal ckdb KeySet
See also:
release()
setKeySet()
Key kdb::KeySet::head ( ) const [inline]
Returns:
alphabetical first key

Return the first key in the KeySet.

The KeySets cursor will not be effected.

If ksCurrent()==ksHead() you know you are on the first key.

Parameters:
ksthe keyset object to work with
Returns:
the first Key of a keyset
0 on NULL pointer or empty keyset
See also:
ksTail() for the last Key
ksRewind(), ksCurrent() and ksNext() for iterating over the KeySet
Key kdb::KeySet::lookup ( const Key key,
const option_t  options = KDB_O_NONE 
) const [inline]

Look for a Key contained in ks that matches the name of the key.

Note:
That the internal key cursor will point to the found key
Key kdb::KeySet::lookup ( std::string const &  name,
const option_t  options = KDB_O_NONE 
) const [inline]

Lookup a key by name.

Parameters:
namethe name to look for
optionssome options to pass
Returns:
the found key
See also:
lookup (const Key &Key, const option_t options)
Note:
That the internal key cursor will point to the found key
Key kdb::KeySet::next ( ) const [inline]

Returns the next Key in a KeySet.

KeySets have an internal cursor that can be reset with ksRewind(). Every time ksNext() is called the cursor is incremented and the new current Key is returned.

You'll get a NULL pointer if the key after the end of the KeySet was reached. On subsequent calls of ksNext() it will still return the NULL pointer.

The ks internal cursor will be changed, so it is not const.

Note:
You must not delete or change the key, use ksPop() if you want to delete it.
Parameters:
ksthe keyset object to work with
Returns:
the new current Key
0 when the end is reached
0 on NULL pointer
See also:
ksRewind(), ksCurrent()
KeySet & kdb::KeySet::operator= ( KeySet const &  other) [inline]

Duplicate a keyset.

This keyset will be a duplicate of the other afterwards.

Note:
that they still reference to the same Keys, so if you change key values also the keys in the original keyset will be changed.
Key kdb::KeySet::pop ( ) [inline]

Remove and return the last key of ks.

The reference counter will be decremented by one.

The KeySets cursor will not be effected if it did not point to the popped key.

Note:
You need to keyDel() the key afterwards, if you don't append it to another keyset. It has the same semantics like a key allocated with keyNew() or keyDup().
ks1=ksNew(0, KS_END);
ks2=ksNew(0, KS_END);

k1=keyNew("user/name", KEY_END); // ref counter 0
ksAppendKey(ks1, k1); // ref counter 1
ksAppendKey(ks2, k1); // ref counter 2

k1=ksPop (ks1); // ref counter 1
k1=ksPop (ks2); // ref counter 0, like after keyNew()

ksAppendKey(ks1, k1); // ref counter 1

ksDel (ks1); // key is deleted too
ksDel (ks2);
 *
Returns:
the last key of ks
NULL if ks is empty or on NULL pointer
Parameters:
ksKeySet to work with
See also:
ksAppendKey(), ksAppend()
commandList() for an example
void kdb::KeySet::rewind ( ) const [inline]

Rewinds the KeySet internal cursor.

Use it to set the cursor to the beginning of the KeySet. ksCurrent() will then always return NULL afterwards. So you want to ksNext() first.

ksRewind (ks);
while ((key = ksNext (ks))!=0) {}
Parameters:
ksthe keyset object to work with
Returns:
0 on success
-1 on NULL pointer
See also:
ksNext(), ksCurrent()
void kdb::KeySet::setCursor ( cursor_t  cursor) const [inline]

Set the KeySet internal cursor.

Use it to set the cursor to a stored position. ksCurrent() will then be the position which you got with.

Warning:
Cursors may get invalid when the key was ksPop()ed or ksLookup() was used together with KDB_O_POP.
cursor_t cursor;
..
// key now in any position here
cursor = ksGetCursor (ks);
while ((key = keyNextMeta (ks))!=0) {}
ksSetCursor (ks, cursor); // reset state
ksCurrent(ks); // in same position as before

An invalid cursor will set the keyset to its beginning like ksRewind(). When you set an invalid cursor ksCurrent() is 0 and ksNext() == ksHead().

Parameters:
cursorthe cursor to use
ksthe keyset object to work with
Returns:
0 when the keyset is ksRewind()ed
1 otherwise
-1 on NULL pointer
See also:
ksNext(), ksGetCursor()
void kdb::KeySet::setKeySet ( ckdb::KeySet *  k) [inline]

Take ownership of passed keyset.

Parameters:
kthe keyset to take ownership from
See also:
release()
getKeySet()
ssize_t kdb::KeySet::size ( ) const [inline]

The size of the keyset.

Returns:
the number of keys in the keyset
Key kdb::KeySet::tail ( ) const [inline]
Returns:
alphabetical last key

Return the last key in the KeySet.

The KeySets cursor will not be effected.

If ksCurrent()==ksTail() you know you are on the last key. ksNext() will return a NULL pointer afterwards.

Parameters:
ksthe keyset object to work with
Returns:
the last Key of a keyset
0 on NULL pointer or empty keyset
See also:
ksHead() for the first Key
ksRewind(), ksCurrent() and ksNext() for iterating over the KeySet

The documentation for this class was generated from the following file: