.TH "key" 3elektra "Thu Sep 7 2023" "Version 0.11.0" "Elektra" \" -*- nroff -*- .ad l .nh .SH NAME key \- Key .PP \- Key is an essential class that encapsulates key \fBname \fP, \fBvalue \fP and \fBmetainfo \fP\&. .SH SYNOPSIS .br .PP .SS "Modules" .in +1c .ti -1c .RI "\fBMeta Info Manipulation Methods\fP" .br .RI "Methods to do various operations on Key metadata\&. " .ti -1c .RI "\fBMethods for Making Tests\fP" .br .RI "Methods to do various tests on Keys\&. " .ti -1c .RI "\fBName Manipulation Methods\fP" .br .RI "Methods to do various operations on Key names\&. " .ti -1c .RI "\fBValue Manipulation Methods\fP" .br .RI "Methods to do various operations on Key values\&. " .in -1c .SS "Macros" .in +1c .ti -1c .RI "#define \fBKDB_PATH_SEPARATOR\fP '/'" .br .RI "\fC/\fP is used to separate key names\&. " .ti -1c .RI "#define \fBKDB_PATH_ESCAPE\fP '\\\\'" .br .RI "\fC\\\fP is used as escape character in the key name\&. " .in -1c .SS "Enumerations" .in +1c .ti -1c .RI "enum \fBelektraKeyFlags\fP { \fBKEY_VALUE\fP = 1 << 1, \fBKEY_FLAGS\fP = 3, \fBKEY_BINARY\fP = 1 << 4, \fBKEY_SIZE\fP = 1 << 11, \fBKEY_META\fP = 1 << 15, \fBKEY_NULL\fP = 1 << 16, \fBKEY_END\fP = 0 }" .br .RI "Allows \fBkeyNew()\fP to determine which information comes next\&. " .ti -1c .RI "enum \fBelektraCopyFlags\fP { \fBKEY_CP_NAME\fP = 1 << 0, \fBKEY_CP_STRING\fP = 1 << 1, \fBKEY_CP_VALUE\fP = 1 << 2, \fBKEY_CP_META\fP = 1 << 3, \fBKEY_CP_ALL\fP = KEY_CP_NAME | KEY_CP_VALUE | KEY_CP_META }" .br .RI "Copy options\&. " .ti -1c .RI "enum \fBelektraLockFlags\fP { \fBKEY_LOCK_NAME\fP = 1 << 17, \fBKEY_LOCK_VALUE\fP = 1 << 18, \fBKEY_LOCK_META\fP = 1 << 19 }" .br .RI "Lock options\&. " .ti -1c .RI "enum \fBelektraNamespace\fP { \fBKEY_NS_NONE\fP = 0, \fBKEY_NS_CASCADING\fP = 1, \fBKEY_NS_META\fP = 2, \fBKEY_NS_SPEC\fP = 3, \fBKEY_NS_PROC\fP = 4, \fBKEY_NS_DIR\fP = 5, \fBKEY_NS_USER\fP = 6, \fBKEY_NS_SYSTEM\fP = 7, \fBKEY_NS_DEFAULT\fP = 8 }" .br .RI "Elektra currently supported Key namespaces\&. " .in -1c .SS "Functions" .in +1c .ti -1c .RI "Key * \fBkeyNew\fP (const char *name,\&.\&.\&.)" .br .RI "A practical way to fully create a Key object in one step\&. " .ti -1c .RI "Key * \fBkeyCopy\fP (Key *dest, const Key *source, \fBelektraCopyFlags\fP flags)" .br .RI "Copy or clear a key\&. " .ti -1c .RI "int \fBkeyDel\fP (Key *key)" .br .RI "A destructor for Key objects\&. " .ti -1c .RI "int \fBkeyClear\fP (Key *key)" .br .RI "Will clear all internal data of a Key\&. " .ti -1c .RI "uint16_t \fBkeyIncRef\fP (Key *key)" .br .RI "Increment the reference counter of a Key object\&. " .ti -1c .RI "uint16_t \fBkeyDecRef\fP (Key *key)" .br .RI "Decrement the reference counter of a Key object\&. " .ti -1c .RI "uint16_t \fBkeyGetRef\fP (const Key *key)" .br .RI "Return the current reference counter value of a Key object\&. " .ti -1c .RI "int \fBkeyLock\fP (Key *key, \fBelektraLockFlags\fP what)" .br .RI "Permanently lock parts of a Key\&. " .ti -1c .RI "int \fBkeyIsLocked\fP (const Key *key, \fBelektraLockFlags\fP what)" .br .RI "Checks which parts of a Key are locked\&. " .in -1c .SH "Detailed Description" .PP Key is an essential class that encapsulates key \fBname \fP, \fBvalue \fP and \fBmetainfo \fP\&. To use it include: .PP .nf #include .fi .PP .PP Key properties are: .IP "\(bu" 2 \fBKey name \fP .IP "\(bu" 2 \fBKey value \fP .IP "\(bu" 2 \fBKey metadata \fP, including but not limited to: .IP " \(bu" 4 \fBKey comment \fP .IP " \(bu" 4 \fBKey owner \fP .IP " \(bu" 4 \fBUID, GID and filesystem-like mode permissions \fP .IP " \(bu" 4 \fBMode, change and modification times \fP .PP .PP .PP \fBABI\fP .RS 4 Due to ABI compatibility, the \fCKey\fP structure is not defined in kdb\&.h, only declared\&. So you can only declare \fCpointers\fP to \fCKeys\fP in your program, and allocate and free memory for them with \fBkeyNew()\fP and \fBkeyDel()\fP respectively\&. .RE .PP \fBReference Counting\fP .RS 4 Every key has its reference counter (see \fBkeyGetRef()\fP for longer explanation) that will be initialized with 0, that means a subsequent call of \fBkeyDel()\fP will delete the key\&. If you append the key to a keyset the reference counter will be incremented by one (see \fBkeyIncRef()\fP) and the key can't be deleted by a \fBkeyDel()\fP\&. .RE .PP \fB\fP .RS 4 As you can imagine this refcounting allows you to put the Key in your own data structures\&. It can be a very powerful feature, e\&.g\&. if you need your own-defined ordering or different Models of your configuration\&. .RE .PP \fBCopy-On-Write\fP .RS 4 Keys employ copy-on-write techniques to minimize memory footprint\&. If keys are copied or duplicated, they will point at the same name and value as the source key\&. Only if this data is changed, additional memory is allocated\&. .RE .PP .SH "Macro Definition Documentation" .PP .SS "#define KDB_PATH_ESCAPE '\\\\'" .PP \fC\\\fP is used as escape character in the key name\&. .PP \fBSee also\fP .RS 4 \fBdescription about key names \fP\&. .RE .PP .SS "#define KDB_PATH_SEPARATOR '/'" .PP \fC/\fP is used to separate key names\&. .PP \fBSee also\fP .RS 4 \fBdescription about key names \fP\&. .RE .PP .SH "Enumeration Type Documentation" .PP .SS "enum \fBelektraCopyFlags\fP" .PP Copy options\&. .PP \fBSee also\fP .RS 4 \fBkeyCopy()\fP .RE .PP .PP \fBEnumerator\fP .in +1c .TP \fB\fIKEY_CP_NAME \fP\fP Flag for copying the key name .TP \fB\fIKEY_CP_STRING \fP\fP Flag for copying the key value, if it is a string .TP \fB\fIKEY_CP_VALUE \fP\fP Flag for copying the key value .TP \fB\fIKEY_CP_META \fP\fP Flag for copying the key metadata .TP \fB\fIKEY_CP_ALL \fP\fP Shorthand for copying name, value and metadata .SS "enum \fBelektraKeyFlags\fP" .PP Allows \fBkeyNew()\fP to determine which information comes next\&. .PP \fBSee also\fP .RS 4 \fBkeyNew()\fP .RE .PP .PP \fBEnumerator\fP .in +1c .TP \fB\fIKEY_VALUE \fP\fP Flag for the key data .TP \fB\fIKEY_FLAGS \fP\fP Allows to define multiple flags at once\&. .TP \fB\fIKEY_BINARY \fP\fP Flag if the key is binary .TP \fB\fIKEY_SIZE \fP\fP Flag for maximum size to limit value .TP \fB\fIKEY_META \fP\fP Flag for metadata .TP \fB\fIKEY_NULL \fP\fP Is \fInot\fP a flag, only as return value .PP \fBDeprecated\fP .RS 4 do not use .RE .PP .TP \fB\fIKEY_END \fP\fP Used as a parameter terminator to \fBkeyNew()\fP .SS "enum \fBelektraLockFlags\fP" .PP Lock options\&. .PP \fBSee also\fP .RS 4 \fBkeyLock()\fP, \fBkeyIsLocked()\fP .RE .PP .PP \fBEnumerator\fP .in +1c .TP \fB\fIKEY_LOCK_NAME \fP\fP lock the name of a key .TP \fB\fIKEY_LOCK_VALUE \fP\fP lock the value of a key .TP \fB\fIKEY_LOCK_META \fP\fP lock the meta data of a key .SS "enum \fBelektraNamespace\fP" .PP Elektra currently supported Key namespaces\&. .PP \fBSee also\fP .RS 4 \fBkdbGet()\fP, \fBkeyGetNamespace()\fP .RE .PP .PP \fBEnumerator\fP .in +1c .TP \fB\fIKEY_NS_NONE \fP\fP no key given as parameter to \fBkeyGetNamespace()\fP .TP \fB\fIKEY_NS_CASCADING \fP\fP cascading key, starts with /, abstract name for any of the namespaces below .TP \fB\fIKEY_NS_META \fP\fP metakey, i\&.e\&. any key name not under other categories .TP \fB\fIKEY_NS_SPEC \fP\fP spec contains the specification of the other namespaces .TP \fB\fIKEY_NS_PROC \fP\fP proc contains process-specific configuration .TP \fB\fIKEY_NS_DIR \fP\fP dir contains configuration from a specific directory .TP \fB\fIKEY_NS_USER \fP\fP user key in the home directory of the current user .TP \fB\fIKEY_NS_SYSTEM \fP\fP system key is shared for a computer system .TP \fB\fIKEY_NS_DEFAULT \fP\fP default key used as a fallback if no other key is found .SH "Function Documentation" .PP .SS "int keyClear (Key * key)" .PP Will clear all internal data of a Key\&. After this call you will receive a fresh Key - with no value, metadata or name\&. .PP The reference counter will stay unmodified\&. .PP \fBNote\fP .RS 4 that you might also clear() all aliases with this operation\&. .RE .PP .PP .nf int f (Key *k) { keyClear (k); // you have a fresh Key k here keySetString (k, "value"); // the caller will get an empty Key k with an value } .fi .PP .PP \fBPostcondition\fP .RS 4 \fCkey's\fP name is '/' .PP \fCkey's\fP metadata is empty .RE .PP \fBParameters\fP .RS 4 \fIkey\fP the Key that should be cleared .RE .PP \fBReturn values\fP .RS 4 \fI0\fP on success .br \fI-1\fP on NULL pointer .RE .PP \fBSince\fP .RS 4 1\&.0\&.0 .RE .PP \fBSee also\fP .RS 4 \fBkeyDel()\fP for completely deleting a Key .RE .PP .SS "Key* keyCopy (Key * dest, const Key * source, \fBelektraCopyFlags\fP flags)" .PP Copy or clear a key\&. Depending on the chosen \fCflags\fP \fBkeyCopy()\fP only copies certain parts of \fCsource\fP into \fCdest\fP\&. .PP .IP "\(bu" 2 If \fBKEY_CP_NAME\fP is set, the key name will be copied from \fCsource\fP to \fCdest\fP\&. .IP "\(bu" 2 If \fBKEY_CP_META\fP is set, the meta keys will be copied from \fCsource\fP to \fCdest\fP\&. .IP "\(bu" 2 If \fBKEY_CP_VALUE\fP is set, the key value will be copied from \fCsource\fP to \fCdest\fP\&. Additionally, if \fCsource\fP is a binary key (\fBkeyIsBinary()\fP), \fCdest\fP will also be marked as binary\&. This means that even if \fBKEY_CP_META\fP is not set, the \fCbinary\fP meta key will be copied with \fBKEY_CP_VALUE\fP\&. .IP "\(bu" 2 If \fBKEY_CP_STRING\fP is set, the key value will be copied from \fCsource\fP to \fCdest\fP, but only, if \fCsource\fP is \fInot\fP a binary key (\fBkeyIsBinary()\fP)\&. If \fCsource\fP is binary, \fBkeyCopy()\fP fails\&. If \fCdest\fP is binary, it will still be marked as binary after the copy\&. This cannot be used together with \fBKEY_CP_VALUE\fP\&. The main purpose of \fBKEY_CP_STRING\fP is for copying \fIinto\fP known string keys\&. It ensure that you don't accidentally convert string keys into binary keys\&. .PP .PP There is also the shorthand \fBKEY_CP_ALL\fP\&. It is equivalent to \fCKEY_CP_NAME | KEY_CP_VALUE | KEY_CP_META\fP, i\&.e\&. all key data supported by \fBkeyCopy()\fP will be copied from \fCsource\fP to \fCdest\fP\&. .PP Use this function when you need to copy into an existing key, e\&.g\&. because it was passed by a pointer in a function you can do so: .PP .PP .nf keyCopy (copy, orig, KEY_CP_ALL); .fi .PP Most often you will want to duplicate an existing key\&. For this purpose the alias keyDup() exists\&. Calling .PP .PP .nf copy = keyDup (orig, KEY_CP_ALL); .fi .PP is equivalent to .PP .PP .nf copy = keyCopy (keyNew ("/", KEY_END), orig, KEY_CP_ALL); .fi .PP The reference counter will not be changed for both keys\&. Affiliation to keysets are also not affected\&. .PP Since metadata uses copy-on-write semantics there is only a constant memory cost to copying metadata\&. .PP When you pass a NULL-pointer as \fCsource\fP the pieces of \fCdest\fP specified by \fCflags\fP will be cleared\&. .PP Calling \fCkeyCopy (dest, NULL, KEY_CP_ALL)\fP is different from calling \fBkeyClear()\fP\&. The key will not be fully reset, the reference counter and internal flags will remain unchanged\&. Additionally, \fBkeyCopy()\fP respects \fBkeyLock()\fP state, while \fBkeyClear()\fP always works\&. .PP .PP .nf keyCopy (k, NULL, KEY_CP_ALL); // name, value and metadata of k have now been clear // lock flags, reference count, etc\&. remain unchanged .fi .PP .PP \fBPrecondition\fP .RS 4 \fCdest\fP must be a valid Key (created with keyNew) .PP \fCdest\fP must not have read-only flags set .PP \fCsource\fP must be a valid Key or NULL .RE .PP \fBInvariant\fP .RS 4 Key name stays valid until delete .RE .PP \fBPostcondition\fP .RS 4 Value from Key source is written to Key dest .RE .PP \fBParameters\fP .RS 4 \fIdest\fP the key which will be written to .br \fIsource\fP the key which should be copied or NULL to clear the data of \fCdest\fP .br \fIflags\fP specifies which parts of the key should be copied .RE .PP \fBReturns\fP .RS 4 \fCdest\fP .RE .PP \fBReturn values\fP .RS 4 \fINULL\fP on memory allocation problems .br \fINULL\fP when a part of \fCdest\fP that should be modified (e\&.g\&. name, value) was marked read-only, e\&.g\&. the name of \fCdest\fP will be read-only if \fCdest\fP is part of a KeySet .br \fINULL\fP when \fCdest\fP is NULL .br \fINULL\fP when both \fBKEY_CP_VALUE\fP and \fBKEY_CP_STRING\fP are set in \fCflags\fP .br \fINULL\fP when both \fBKEY_CP_STRING\fP is set in \fCflags\fP and \fCsource\fP is a binary key (\fBkeyIsBinary()\fP) .RE .PP \fBSince\fP .RS 4 0\&.9\&.5 .RE .PP \fBSee also\fP .RS 4 keyDup() for duplicating an existing Key .RE .PP .SS "uint16_t keyDecRef (Key * key)" .PP Decrement the reference counter of a Key object\&. As long as the reference counter is non-zero, \fC\fBkeyDel()\fP\fP operations on \fCkey\fP will be a no-op and return an error code\&. .PP \fBPostcondition\fP .RS 4 \fCkey's\fP reference counter is >= 0 .PP \fCkey's\fP reference counter is < SSIZE_MAX .RE .PP \fBParameters\fP .RS 4 \fIkey\fP the Key object whose reference counter should get decreased .RE .PP \fBReturns\fP .RS 4 the updated value of the reference counter .RE .PP \fBReturn values\fP .RS 4 \fIUINT16_MAX\fP on NULL pointer .br \fI0\fP when the reference counter already was the minimum value 0, the reference counter will not be modified in this case .RE .PP \fBSince\fP .RS 4 1\&.0\&.0 .RE .PP \fBSee also\fP .RS 4 \fBkeyGetRef()\fP to retrieve the current reference count .PP \fBkeyIncRef()\fP for increasing the reference counter and for a more complete explanation of the reference counting system .PP \fBkeyDel()\fP for deleting a Key .RE .PP .SS "int keyDel (Key * key)" .PP A destructor for Key objects\&. Every Key created by \fBkeyNew()\fP must be deleted with \fBkeyDel()\fP\&. .PP When the reference counter of \fCkey\fP is non-zero, this function will do nothing and simply return the current value of the reference counter\&. .PP It is therefore safe to call \fCkeyDel (k)\fP on any \fCKey * k\fP\&. .PP \fBPostcondition\fP .RS 4 all memory related to \fCkey\fP will be freed .RE .PP \fBParameters\fP .RS 4 \fIkey\fP the Key object to delete .RE .PP \fBReturn values\fP .RS 4 \fI0\fP when the Key was freed .br \fI-1\fP on NULL pointers .RE .PP \fBReturns\fP .RS 4 the value of the reference counter, if it was non-zero .RE .PP \fBSince\fP .RS 4 1\&.0\&.0 .RE .PP \fBSee also\fP .RS 4 \fBkeyNew()\fP for creating a new Key .PP \fBkeyIncRef()\fP for more information about the reference counter .RE .PP .SS "uint16_t keyGetRef (const Key * key)" .PP Return the current reference counter value of a Key object\&. .PP \fBParameters\fP .RS 4 \fIkey\fP the Key whose reference counter to retrieve .RE .PP \fBReturns\fP .RS 4 the value of the \fCkey's\fP reference counter .RE .PP \fBReturn values\fP .RS 4 \fI-1\fP on NULL pointer .RE .PP \fBSince\fP .RS 4 1\&.0\&.0 .RE .PP \fBSee also\fP .RS 4 \fBkeyIncRef()\fP for increasing the reference counter and for a more complete explanation of the reference counting system .PP \fBkeyDecRef()\fP for decreasing the reference counter .RE .PP .SS "uint16_t keyIncRef (Key * key)" .PP Increment the reference counter of a Key object\&. As long as the reference counter is non-zero, \fC\fBkeyDel()\fP\fP operations on \fCkey\fP will be a no-op and return an error code\&. .PP Elektra's system for reference counting is not based on a concept of shared ownership\&. It is more similar to a shared lock, where the counter is used to keep track of how many clients hold the lock\&. .PP Initially, the reference counter will be 0\&. This is can be interpreted as the lock being unlocked\&. When you increment the reference counter, the lock becomes locked and \fC\fBkeyDel()\fP\fP is blocked and fails\&. Only when the reference counter is fully decremented back down to 0 again, will \fC\fBkeyDel()\fP\fP work again\&. .PP \fBNote\fP .RS 4 The reference counter can never exceed \fCUINT16_MAX - 1\fP\&. \fCUINT16_MAX\fP is reserved as an error code\&. .RE .PP \fBPostcondition\fP .RS 4 \fCkey's\fP reference counter is > 0 .PP \fCkey's\fP reference counter is <= UINT16_MAX - 1 .RE .PP \fBParameters\fP .RS 4 \fIkey\fP the Key object whose reference counter should be increased .RE .PP \fBReturns\fP .RS 4 the updated value of the reference counter .RE .PP \fBReturn values\fP .RS 4 \fIUINT16_MAX\fP on NULL pointer .br \fIUINT16_MAX\fP when the reference counter already was the maximum value \fCUINT16_MAX - 1\fP, the reference counter will not be modified in this case .RE .PP \fBSince\fP .RS 4 1\&.0\&.0 .RE .PP \fBSee also\fP .RS 4 \fBkeyGetRef()\fP to retrieve the current reference count .PP \fBkeyDecRef()\fP for decreasing the reference counter .PP \fBkeyDel()\fP for deleting a Key .RE .PP .SS "int keyIsLocked (const Key * key, \fBelektraLockFlags\fP what)" .PP Checks which parts of a Key are locked\&. .PP \fBParameters\fP .RS 4 \fIkey\fP the Key that should be checked for locks .br \fIwhat\fP the parts of the Key that should checked for locks .RE .PP \fBReturns\fP .RS 4 the bits that are locked .RE .PP \fBReturn values\fP .RS 4 \fI0\fP if nothing is locked .br \fI-1\fP on error (NULL pointer) .RE .PP \fBSince\fP .RS 4 1\&.0\&.0 .RE .PP \fBSee also\fP .RS 4 \fBkeyLock()\fP for locking a Key .RE .PP .SS "int keyLock (Key * key, \fBelektraLockFlags\fP what)" .PP Permanently lock parts of a Key\&. This can be: .IP "\(bu" 2 KEY_LOCK_NAME to lock the name .IP "\(bu" 2 KEY_LOCK_VALUE to lock the value .IP "\(bu" 2 KEY_LOCK_META to lock the metadata .PP .PP To unlock the Key, duplicate it\&. .PP It is also possible to lock the Key when it is created with \fBkeyNew()\fP\&. .PP Some data structures need to lock the Key (most likely its name), so that the ordering does not get confused\&. .PP \fBPostcondition\fP .RS 4 keyIsLocked(key, what) == what .RE .PP \fBParameters\fP .RS 4 \fIkey\fP the Key that should be locked .br \fIwhat\fP the parts of the Key that should be locked (see above) .RE .PP \fBReturns\fP .RS 4 the bits that were successfully locked .RE .PP \fBReturn values\fP .RS 4 \fI0\fP if everything was locked before .br \fI-1\fP if it could not be locked (NULL pointer) .RE .PP \fBSince\fP .RS 4 1\&.0\&.0 .RE .PP \fBSee also\fP .RS 4 \fBkeyIsLocked()\fP for checking whether a Key is locked .PP \fBkeyNew()\fP for creating a new Key .PP keyDup() for duplicating an existing Key .PP \fBksAppendKey()\fP appends a Key to a \fBKeySet\fP (and locks it) .RE .PP .SS "Key* keyNew (const char * name, \&.\&.\&.)" .PP A practical way to fully create a Key object in one step\&. To just get a key object, simple do: .PP .PP .nf // Create and initialize a key with a name and nothing else Key *k=keyNew("user:/some/example", KEY_END); // work with it keyDel (k); .fi .PP \fBkeyNew()\fP allocates memory for a key object and \fBkeyDel()\fP cleans everything up\&. .PP If you want the key object to contain a name, value, comment and other meta info read on\&. .PP \fBNote\fP .RS 4 When you already have a key with similar properties its easier to keyDup() the key\&. .RE .PP You can call \fBkeyNew()\fP in many different ways depending on the attribute tags you pass as parameters\&. Tags are represented as \fBelektraKeyFlags\fP values, and tell \fBkeyNew()\fP which Key attribute comes next\&. The Key attribute tags are the following: .IP "\(bu" 2 \fBKEY_VALUE\fP .br Next parameter is a pointer to the value that will be used\&. If no \fBKEY_BINARY\fP was used before, a string is assumed\&. .PP .nf // Create and initialize a key with a name and nothing else Key *k=keyNew("user:/tmp/ex0", KEY_VALUE, "some data", // set a string value KEY_END); // end of args .fi .PP .IP "\(bu" 2 \fBKEY_SIZE\fP .br Define a maximum length of the value\&. This is only used when setting a binary key\&. .PP .nf // Create and initialize a key with a name and nothing else Key *k=keyNew("user:/tmp/ex1", KEY_SIZE, 4, // has no effect on strings KEY_VALUE, "some data", // set a string value KEY_END); // end of args .fi .PP .IP "\(bu" 2 \fBKEY_META\fP .br Next two parameter is a metaname and a metavalue\&. See \fBkeySetMeta()\fP\&. .PP .nf Key *k=keyNew("user:/tmp/ex3", KEY_META, "comment/#0", "a comment", // with a comment KEY_META, "owner", "root", // and an owner KEY_META, "special", "yes", // and any other metadata KEY_END); // end of args .fi .PP .IP "\(bu" 2 \fBKEY_END\fP .br Must be the last parameter passed to \fBkeyNew()\fP\&. It is always required, unless the \fCkeyName\fP is 0\&. .IP "\(bu" 2 \fBKEY_FLAGS\fP .br Bitwise disjunction of flags, which don't require one or more values\&. recommended way to set multiple flags\&. overrides previously defined flags\&. .PP .nf Key *k=keyNew("user:/tmp/ex3", KEY_BINARY, // binary key KEY_SIZE, 7, // assume binary length 7 KEY_VALUE, "some data", // value that will be truncated in 7 bytes KEY_END); // end of args .fi .PP .IP "\(bu" 2 \fBKEY_BINARY\fP .br Allows one to change the key to a binary key\&. Make sure that you also pass \fBKEY_SIZE\fP before you set the value\&. Otherwise it will be cut off with first \\0 in the string\&. So this flag toggle from \fBkeySetString()\fP to \fBkeySetBinary()\fP\&. If no value (nor size) is given, it will be a NULL key\&. .PP .nf // Create and initialize a key with a name and nothing else Key *k=keyNew("user:/tmp/ex2", KEY_BINARY, KEY_SIZE, 4, // now the size is important KEY_VALUE, "some data", // sets the binary value ("some") KEY_END); // end of args .fi .PP .PP .PP .nf Key *k=keyNew("user:/tmp/ex4", KEY_BINARY, // key type KEY_SIZE, 7, // assume binary length 7 KEY_VALUE, "some data", // value that will be truncated in 7 bytes KEY_META, "comment/#0", "value is truncated", KEY_END); // end of args .fi .PP .PP \fBPrecondition\fP .RS 4 \fCname\fP is a valid Key name .PP Variable arguments are a valid combination .RE .PP \fBPostcondition\fP .RS 4 returns a new, fully initialized Key object with the valid Key name and all data given by variable arguments .RE .PP \fBParameters\fP .RS 4 \fIname\fP a valid name to the key (see \fBkeySetName()\fP) .RE .PP \fBReturns\fP .RS 4 a pointer to a new allocated and initialized Key object\&. .RE .PP \fBReturn values\fP .RS 4 \fINULL\fP on allocation error or if an invalid \fCname\fP was passed (see \fBkeySetName()\fP)\&. .RE .PP \fBSince\fP .RS 4 1\&.0\&.0 .RE .PP \fBSee also\fP .RS 4 \fBkeyDel()\fP for deallocating a created Key object .PP \fBkeySetName()\fP for rules about which names are considered valid .RE .PP .PP .SH "Author" .PP Generated automatically by Doxygen for Elektra from the source code\&.