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%IO.FileStream

class %IO.FileStream extends %IO.DeviceStream, %IO.IParts.CharacterSeekableIO

Property Inventory (Including Private)

Method Inventory (Including Private)

Parameters

parameter DEFTEMPFILEEXT = iostream;
parameter READ = R;
final parameter RWREADCHANGED = 2;
final parameter RWREADNODATA = 0;
final parameter RWREADNOTCHANGED = 1;
final parameter RWWRITE = 3;
parameter WRITE = W;
parameter WRITEAPPEND = A;
parameter WRITENEWIFABSENT = E;
parameter WRITENEWOVER = N;

Properties

property %Mode as %String (TRUNCATE = 1) [ ReadOnly ];
Property methods: %ModeDisplayToLogical(), %ModeGet(), %ModeIsValid(), %ModeLogicalToDisplay(), %ModeLogicalToOdbc(), %ModeNormalize()
property %RWMode as %Boolean [ Private ];
Property methods: %RWModeDisplayToLogical(), %RWModeGet(), %RWModeIsValid(), %RWModeLogicalToDisplay(), %RWModeNormalize(), %RWModeSet()
property %ReadLineMode as %Boolean [ ReadOnly ];
Property methods: %ReadLineModeDisplayToLogical(), %ReadLineModeGet(), %ReadLineModeIsValid(), %ReadLineModeLogicalToDisplay(), %ReadLineModeNormalize()
property BuildCharPosMap as %Boolean [ InitialExpression = 1 ];
Flag to control whether the stream object should maintain the charposmap map between character positions and external byte positions when the file is opened using a multibyte character encoding. This flag is ignored when the character set only contains single-bye characters. The flag is initialized to 0 when a file is not opened with the READ flag, but can always be modified by the user after Open()() has been called.
Property methods: BuildCharPosMapDisplayToLogical(), BuildCharPosMapGet(), BuildCharPosMapIsValid(), BuildCharPosMapLogicalToDisplay(), BuildCharPosMapNormalize(), BuildCharPosMapSet()
property IsTemp as %Boolean;
Property methods: IsTempDisplayToLogical(), IsTempGet(), IsTempIsValid(), IsTempLogicalToDisplay(), IsTempNormalize(), IsTempSet()
property LastModified as %TimeStamp [ Calculated ];
Property methods: LastModifiedDisplayToLogical(), LastModifiedGet(), LastModifiedIsValid(), LastModifiedLogicalToDisplay(), LastModifiedNormalize(), LastModifiedOdbcToLogical()
property charposmap [ Private , MultiDimensional ];
Map of byte positions to character positions
Property methods: charposmapDisplayToLogical(), charposmapGet(), charposmapIsValid(), charposmapLogicalToDisplay(), charposmapLogicalToOdbc(), charposmapNormalize(), charposmapSet()

Methods

private method %OnNew(initvalue As %CacheString) as %Status
Inherited description: This callback method is invoked by the %New() method to provide notification that a new instance of an object is being created.

If this method returns an error then the object will not be created.

It is passed the arguments provided in the %New call. When customizing this method, override the arguments with whatever variables and types you expect to receive from %New(). For example, if you're going to call %New, passing 2 arguments, %OnNew's signature could be:

Method %OnNew(dob as %Date = "", name as %Name = "") as %Status If instead of returning a %Status code this returns an oref and this oref is a subclass of the current class then this oref will be the one returned to the caller of %New method.

method Close(Output pSC As %Status) as %Boolean
Inherited description: Close the current stream
method ExternalByteSeek(pBytePos As %Integer, Output pSC As %Status) as %Boolean
method ExternalByteSizeGet() as %Integer
method ExternalByteTruncateAt(pBytePos As %Integer, Output pSC As %Status) as %Boolean
method Flush(Output pSC As %Status)
Ensure that any data already written to the stream buffer is sent to the stream.

In addition a reopen of the file takes place.

Note: The Flush method does not ensure that data actually gets flushed to disk. Using the traditional COS "W *-3" to a device ensures that this occurs.

method LastModifiedGet() as %TimeStamp
classmethod NewTempFilename(tExt As %String = "", pUseTempDir As %Boolean = 0, pDirectory As %String = "") as %String
Create a new, unused filename. By default, the returned filename will have no directory component and will have the default file extension specified in DEFTEMPFILEEXT. If tExt is specified, this will be used as the file extension. If pUseTempDir is true, then the filename will include the current temporary directory for the namespace in which the method is called. If pDirectory is specified, the supplied directory name will be used irrespective of the value of pUseTempDir.
method Open(pName As %String = "", pMode As %String = "R", ByRef pTimeout As %Numeric = 0, pCharEncoding As %String = "Native", Output pSC As %Status) as %Boolean
method Read(pMaxReadLen As %Integer, ByRef pTimeout As %Numeric = -1, Output pSC As %Status) as %String
Inherited description: Read until pMaxReadLen chars are gotten or pTimeout expires On return, if pTimeout is unchanged it means the full timeout period expired. If the timeout period expired and the returned string is shorter than pMaxReadLen, then AtEnd will be 1.
method ReadLine(pMaxReadLen As %Integer, ByRef pTimeout As %Numeric = -1, Output pSC As %Status, ByRef pLineTerminator As %String = ..LineTerminator) as %String
Inherited description: Read until pMaxReadLen chars are gotten, pTimeout expires, or a LineTerminator character is found. On return, if pTimeout=0 it means no timeout occurred. If pTimeout=0 and the returned string contains the full pMaxReadLen characters, it means no LineTerminator was encountered yet, even if the following character would be a LineTerminator. If pTimeout=0 and the returned string is shorter than pMaxReadLen, then either a LineTerminator or the End Of Stream (AtEnd = 1) was encountered. If pLineTerminator is defined, then the line is read until one of the given characters is encountered. On return, pLineTerminator contains the encountered character(s) if any.
method Seek(pPosition As %Integer = 1, Output pSC As %Status) as %Boolean
method SizeGet() as %Integer
Return the current character size of the data stream.
method TruncateAt(pPosition As %Integer, Output pSC As %Status) as %Boolean
method Write(pData As %String = "", pFlush As %Boolean, Output pSC As %Status)
Inherited description: Write pData to the stream buffer. If pFlush is True, ensure that the data are actually sent to the stream.
private method reopen(pReadLineMode As %Boolean, pForce As %Boolean, pLineTerminator As %String, ByRef pTimeout As %Numeric = 0, ByRef pSize As %Integer = 0) as %Boolean

Inherited Members

Inherited Properties (Including Private)

Inherited Methods (Including Private)

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