Cache Tcl Reference Documentation

Cache

Current Version: 9.5.0.97

Object Creation

set myCache [new CkCache]

Properties

DebugLogFilePath
string
# ckStr is a CkString
CkCache_get_DebugLogFilePath $myCache $ckStr
set strVal [CkCache_get_debugLogFilePath $myCache]
CkCache_put_DebugLogFilePath $myCache $strVal

If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.

This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:

  1. a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
  2. the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
  3. there is an internal problem (bug) in the Chilkat code that causes the hang.

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LastErrorHtml
string
# ckStr is a CkString
CkCache_get_LastErrorHtml $myCache $ckStr
set strVal [CkCache_get_lastErrorHtml $myCache]

Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

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LastErrorText
string
# ckStr is a CkString
CkCache_get_LastErrorText $myCache $ckStr
set strVal [CkCache_get_lastErrorText $myCache]

Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

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LastErrorXml
string
# ckStr is a CkString
CkCache_get_LastErrorXml $myCache $ckStr
set strVal [CkCache_get_lastErrorXml $myCache]

Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

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LastEtagFetched
string
# ckStr is a CkString
CkCache_get_LastEtagFetched $myCache $ckStr
set strVal [CkCache_get_lastEtagFetched $myCache]

The ETag of the last item fetched from cache.

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LastExpirationFetchedStr
string
# ckStr is a CkString
CkCache_get_LastExpirationFetchedStr $myCache $ckStr
set strVal [CkCache_get_lastExpirationFetchedStr $myCache]

Expiration date/time of the last item fetched from cache in RFC822 string format.

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LastHitExpired
boolean 1/0
set boolVal [CkCache_get_LastHitExpired $myCache]

1 if the LastExpirationFetched is before the current date/time. Otherwise 0.

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LastKeyFetched
string
# ckStr is a CkString
CkCache_get_LastKeyFetched $myCache $ckStr
set strVal [CkCache_get_lastKeyFetched $myCache]

The key of the last item fetched from cache. (For web pages, the key is typically the canonicalized URL. Otherwise, the key is a unique identifer used to access the cached item.)

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LastMethodSuccess
boolean 1/0
set boolVal [CkCache_get_LastMethodSuccess $myCache]
CkCache_put_LastMethodSuccess $myCache $boolVal

Indicate whether the last method call succeeded or failed. A value of 1 indicates success, a value of 0 indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:

  • Any method that returns a string.
  • Any method returning a Chilkat object, binary bytes, or a date/time.
  • Any method returning a standard boolean status value where success = 1 and failure = 0.
  • Any method returning an integer where failure is defined by a return value less than zero.

Note: Methods that do not fit the above requirements will always set this property equal to 1. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

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Level
integer
set intVal [CkCache_get_Level $myCache]
CkCache_put_Level $myCache $intVal

The number of directory levels in the cache. Possible values are:

0: All cache files are in a single directory (the cache root).

1: Cache files are located in 256 sub-directories numbered 0 .. 255 directly under the cache root.

2: There are two levels of sub-directories under the cache root. The 1st level has 256 sub-directories numbered 0 .. 255 directly under the cache root. The 2nd level allows for up to 256 sub-directories (0..255) under each level-1 directory. Cache files are stored in the leaf directories.

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NumRoots
integer
set intVal [CkCache_get_NumRoots $myCache]

The number of root directories composing the cache. A typical multi-root cache would place each root on a separate hard drive.

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Utf8
boolean 1/0
set boolVal [CkCache_get_Utf8 $myCache]
CkCache_put_Utf8 $myCache $boolVal

When set to 1, all "const char *" arguments are interpreted as utf-8 strings. If set to 0 (the default), then "const char *" arguments are interpreted as ANSI strings. Also, when set to 1, and Chilkat method returning a "const char *" is returning the utf-8 representation. If set to 0, all "const char *" return values are ANSI strings.

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VerboseLogging
boolean 1/0
set boolVal [CkCache_get_VerboseLogging $myCache]
CkCache_put_VerboseLogging $myCache $boolVal

If set to 1, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is 0. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

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Version
string
# ckStr is a CkString
CkCache_get_Version $myCache $ckStr
set strVal [CkCache_get_version $myCache]

Version of the component/library, such as "9.5.0.94"

More Information and Examples
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Methods

AddRoot
# path is a string
CkCache_AddRoot $path

Must be called once for each cache root. For example, if the cache is spread across D:\cacheRoot, E:\cacheRoot, and F:\cacheRoot, an application would setup the cache object by calling AddRoot three times -- once with "D:\cacheRoot", once with "E:\cacheRoot", and once with "F:\cacheRoot".

More Information and Examples
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DeleteAll
set retInt [CkCache_DeleteAll]

Deletes all items in the cache. This method completely clears the cache. All files in the cache are deleted. (If the cache is multi-level, existing sub-directories are not deleted.)

Returns the number of items (i.e. cache files) deleted.

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DeleteAllExpired
set retInt [CkCache_DeleteAllExpired]

Deletes all expired items from the cache.

Returns the number of items (i.e. cache files) deleted.

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DeleteFromCache
# key is a string
set status [CkCache_DeleteFromCache $key]

Deletes a single item from the disk cache. Returns 0 if the item exists in cache but could not be deleted. Otherwise returns 1.

Returns 1 for success, 0 for failure.

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DeleteOlderDt
# dateTime is a CkDateTime
set retInt [CkCache_DeleteOlderDt $dateTime]

The same as DeleteOlder, except the dateTime is passed as a CkDateTime.

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DeleteOlderStr
# dateTimeStr is a string
set retInt [CkCache_DeleteOlderStr $dateTimeStr]

The same as DeleteOlder, except the dateTimeStr is passed as a date/time in RFC822 format.

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FetchBd
# key is a string
# bd is a CkBinData
set status [CkCache_FetchBd $key $bd]
Introduced in version 9.5.0.91

Fetches an item from cache and returns in bd.

The key may be any length and may include any characters. It should uniquely identify the cached item. (No two items in the cache should have the same key.)

Returns 1 for success, 0 for failure.

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FetchFromCache
# key is a string
# outBytes is a CkByteData (output)
set status [CkCache_FetchFromCache $key $outData]

Fetches an item from cache.

The key may be any length and may include any characters. It should uniquely identify the cached item. (No two items in the cache should have the same key.)

Returns 1 for success, 0 for failure.

More Information and Examples
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FetchSb
# key is a string
# sb is a CkStringBuilder
set status [CkCache_FetchSb $key $sb]
Introduced in version 9.5.0.91

Fetches a text item from the cache and returns in sb.

The key may be any length and may include any characters. It should uniquely identify the cached item. (No two items in the cache should have the same key.)

Returns 1 for success, 0 for failure.

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FetchText
# key is a string
# outStr is a CkString (output)
set status [CkCache_FetchText $key $outStr]
set retStr [CkCache_fetchText $myCache $key]

Fetches a text item from the cache and returns it's text content.

The key may be any length and may include any characters. It should uniquely identify the cached item. (No two items in the cache should have the same key.)

Returns 1 for success, 0 for failure.

More Information and Examples
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GetEtag
# key is a string
# outStr is a CkString (output)
set status [CkCache_GetEtag $key $outStr]
set retStr [CkCache_getEtag $myCache $key]

Returns the eTag for an item in the cache.

Returns 1 for success, 0 for failure.

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GetExpirationDt
# returns a CkDateTime
# key is a string
set ret_ckDateTime [CkCache_GetExpirationDt $key]

Returns the expiration date/time for an item in the cache as a CkDateTime object.

Returns NULL on failure

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GetExpirationStr
# url is a string
# outStr is a CkString (output)
set status [CkCache_GetExpirationStr $url $outStr]
set retStr [CkCache_getExpirationStr $myCache $url]

Returns the expiration date/time for an item in the cache in RFC822 string format.

Returns 1 for success, 0 for failure.

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GetFilename
# key is a string
# outStr is a CkString (output)
set status [CkCache_GetFilename $key $outStr]
set retStr [CkCache_getFilename $myCache $key]

Returns the absolute file path of the cache file associated with the key.

Returns 1 for success, 0 for failure.

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GetRoot
# index is an integer
# outStr is a CkString (output)
set status [CkCache_GetRoot $index $outStr]
set retStr [CkCache_getRoot $myCache $index]

Returns the directory path of the Nth cache root. (Indexing begins at 0.)

Returns 1 for success, 0 for failure.

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IsCached
# key is a string
set retBool [CkCache_IsCached $key]

Returns 1 if the item is found in the cache, otherwise returns 0.

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SaveTextDt
# key is a string
# expireDateTime is a CkDateTime
# eTag is a string
# itemTextData is a string
set status [CkCache_SaveTextDt $key $expireDateTime $eTag $itemTextData]

The same as SaveText, except the expire date/time is passed as a CkDateTime object.

Returns 1 for success, 0 for failure.

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SaveTextNoExpire
# key is a string
# eTag is a string
# itemTextData is a string
set status [CkCache_SaveTextNoExpire $key $eTag $itemTextData]

Inserts or replaces an text item in the cache with no expiration date/time. The eTag is optional and may be set to a zero-length string. Applications may use it as a place to save additional information about the cached item.

Returns 1 for success, 0 for failure.

More Information and Examples
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SaveTextStr
# key is a string
# expireDateTime is a string
# eTag is a string
# itemTextData is a string
set status [CkCache_SaveTextStr $key $expireDateTime $eTag $itemTextData]

The same as SaveText, except the expire date/time is passed as a string in RFC822 format.

Returns 1 for success, 0 for failure.

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SaveToCacheDt
# key is a string
# expireDateTime is a CkDateTime
# eTag is a string
# itemData is a CkByteData
set status [CkCache_SaveToCacheDt $key $expireDateTime $eTag $itemData]

The same as SaveToCache, except the expire date/time is passed as a CkDateTime object.

Returns 1 for success, 0 for failure.

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SaveToCacheNoExpire
# key is a string
# eTag is a string
# itemData is a CkByteData
set status [CkCache_SaveToCacheNoExpire $key $eTag $itemData]

Inserts or replaces an item in the cache. The cached item will have no expiration. The eTag is optional and may be set to a zero-length string. Applications may use it as a place to save additional information about the cached item.

Returns 1 for success, 0 for failure.

More Information and Examples
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SaveToCacheStr
# key is a string
# expireDateTime is a string
# eTag is a string
# itemData is a CkByteData
set status [CkCache_SaveToCacheStr $key $expireDateTime $eTag $itemData]

The same as SaveToCache, except the expire date/time is passed in RFC822 string format.

Returns 1 for success, 0 for failure.

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UpdateExpirationDt
# key is a string
# expireDateTime is a CkDateTime
set status [CkCache_UpdateExpirationDt $key $expireDateTime]

The same as UpdateExpiration, except the expireDateTime is passed as a CkDateTime.

Returns 1 for success, 0 for failure.

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UpdateExpirationStr
# key is a string
# expireDateTime is a string
set status [CkCache_UpdateExpirationStr $key $expireDateTime]

The same as UpdateExpiration, except the expireDateTime is passed in RFC822 string format.

Returns 1 for success, 0 for failure.

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