Class Reference
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stream class %Library.File extends %AbstractStream

The %File class represents a disk file. It contains a number of class methods that provide a number of file system services.

For example,

	If ##class(%File).Exists("file.txt") Write "It exists",!

You can also create an instance of a %File object that represents a particular file. %File makes a number of file attributes accessible as properties as well as providing a %AbstractStream interface on the file.

For example,

	Set file=##class(%File).%New("file.txt")
	Write file.Size
	Do file.Open("WSN")
	Do file.WriteLine("This is a line of text")
Note that this class is a fairly simple wrapper around the Caché file commands. For simply reading/writing to a file it is suggested that you look at the %Stream.FileCharacter and %Stream.FileBinary classes. These open the file using the correct mode automatically in order to read or write to the file and so are simpler to use.

Inventory

Parameters Properties Methods Queries Indices ForeignKeys Triggers
6 67 3


Summary

Properties
%Location AtEnd Attributes CanonicalName DateCreated
DateModified Id IsOpen LastModified LineTerminator
Name Size

Methods
%AddToSaveSet %CheckUnique %ClassIsLatestVersion %ClassName
%ConstructClone %Delete %DeleteExtent %DeleteId
%DispatchClassMethod %DispatchGetModified %DispatchGetProperty %DispatchMethod
%DispatchSetModified %DispatchSetMultidimProperty %DispatchSetProperty %Exists
%ExistsId %Extends %GetParameter %GetSwizzleObject
%Id %IsA %IsModified %IsNull
%KillExtent %LOBPrefetch %LocationSet %LockStream
%New %NormalizeObject %ObjectIsNull %ObjectModified
%ObjectSize %Oid %Open %OpenId
%OriginalNamespace %PackageName %ReleaseLock %Reload
%RemoveFromSaveSet %RollBack %Save %SerializeObject
%SetModified %UnlockStream %ValidateObject Attributes
CanonicalFilename CanonicalNameGet Clear Close
Compare ComplexDelete ComputeFullDBDir CopyDir
CopyFile CopyFrom CopyFromAndSave CreateDirectory
CreateDirectoryChain CreateNewDir DateCreatedGet DateModifiedGet
Delete DeleteAttribute DeleteStream DirectoryExists
DriveListClose DriveListExecute DriveListFetch Exists
FileSetClose FileSetExecute FileSetFetch FindAt
Flush GetAttribute GetAttributeList GetDirectory
GetDirectoryLength GetDirectoryPiece GetDirectorySpace GetFileDateCreated
GetFileDateModified GetFileSize GetFilename GetStreamId
InputFromDevice IsCharacter IsDefinedAttribute IsNull
LastModifiedGet LineTerminatorSet ManagerDirectory MoveTo
MoveToEnd NextAttribute NormalizeDirectory NormalizeFilename
NormalizeFilenameWithSpaces Open OpenStream OutputToDevice
OutputToDeviceAt ParentDirectoryName ParseDirectoryClose ParseDirectoryExecute
ParseDirectoryFetch Read ReadLine ReadLineIntoStream
ReadOnly ReadSQL RemoveDirectory RemoveDirectoryTree
Rename Rewind SHA1Hash SaveStream
SerializeToSyncSet SetAttribute SetAttributeList SetAttributes
SetReadOnly SetUMask SetWriteable SizeGet
StreamOIDIsNull SubDirectoryName SyncStreamIn TempFilename
VMSRecordFormat Write WriteLine Writeable


Properties

• property CanonicalName as %String(MAXLEN=5000) [ Calculated ];
Read only property that returns the canonical filename if the file is open and "" if the file is not open. On VMS this will include the file version number
• property DateCreated as %Date [ Calculated ];
The creation date for this file (rounded to the second).
• property DateModified as %Date [ Calculated ];
The last modified date for this file (rounded to the second).
• property IsOpen as %Boolean [ InitialExpression = 0 ];
True (1) if this file is currently open, false (0) otherwise.
• property Name as %String(MAXLEN=5000);
The name of this file.

Methods

• classmethod Attributes(filename As %String) as %String
Return the attributes of the file. The format of the returned value depends on the underlying operating system.

Microsoft Windows® returns a value as a combination of bits whose meaning is:

  • 1: 0x00001 - Read-only
  • 2: 0x00002 - Hidden
  • 4: 0x00004 - System
  • 8: 0x00008 - Unused
  • 16: 0x00010 - Directory
  • 32: 0x00020 - Archive
  • 64: 0x00040 - Device
  • 128: 0x00080 - Normal
  • 256: 0x00100 - Temporary
  • 512: 0x00200- Sparse File
  • 1024: 0x00400 - Reparse Point
  • 2048: 0x00800 - Compressed
  • 4096: 0x01000 - Offline
  • 8192: 0x02000 - Content Not Indexed
  • 16384: 0x04000 - Encrypted
  • 32768: 0x08000 - Unused
  • 65536: 0x10000 - Virtual

In UNIX®, the returned value represents the mode map:

  • 1: 0x0001 - execute permission for others
  • 2: 0x0002 - write permission for others
  • 4: 0x0004 - read permission for others
  • 7: 0x0007 - mask for others permissions
  • 8: 0x0008 - execute permission for group
  • 16: 0x0010 - write permission for group
  • 32: 0x0020 - read permission for group
  • 56: 0x0038 - mask for group permissions
  • 64: 0x0040 - execute permission for owner
  • 128: 0x0080 - write permission for owner
  • 256: 0x0100 - read permission for owner
  • 448: 0x01C0 - mask for file owner permissions
  • 512: 0x0200 - sticky bit
  • 1024: 0x0400 - set groupid
  • 2048: 0x0800 - set userid
  • 4096: 0x1000 - fifo
  • 8192: 0x2000 - character device
  • 16384: 0x4000 - directory
  • 24576: 0x6000 - block device
  • 32768: 0x8000 - regular file
  • 40960: 0xA000 - symbolic link
  • 49152: 0xC000 - socket
  • 61440: 0xF000 - mask for file type

On OpenVMS, this is the file protection presented as four 4-bit fields, accessed by the following hexadecimal masks:

  • 000F: system privileges
  • 00F0: owner privileges
  • 0F00: group privileges
  • F000: world privileges
where each of these subfields has bit values with the following meanings:
  • 1: no read access
  • 2: no write access
  • 4: no execute access
  • 8: no delete access

Note: Individual Operating System vendor differences may exist. The relevant man/help pages or other associated documentation should be consulted for a definitive description of the file attributes on a given system.

• classmethod CanonicalFilename(filename As %String) as %String
VMS specific function, returns the canonical form of the filename, on VMS this will include the version number. If the file can not be opened then it will return ""
• method CanonicalNameGet() as %String
This is a Get accessor method for the CanonicalName property.
• method Clear() as %Status
Clear the contents of this Stream from permanent storage. This will remove the permanent stream storage and any temporary stream and initialise the stream to its initial state that it starts in, including removing all the stream attributes.

Returns a %Status value indicating success or failure.

• method Close()
Close the current file.
• classmethod Compare(file1 As %String, file2 As %String) as %Boolean
Compare two files and return 1 if they are identical and 0 otherwise
• classmethod ComplexDelete(filename As %String, Output return As %Integer) as %Integer
Handle delete of cases where filename contains a wildcard. Note: this does not delete subdirectories in the given directory; only files are removed. Pass return by reference to obtain the low level return value in case of errors
• classmethod ComputeFullDBDir(filename As %String) as %String
Return the canonical form of the directory name filename. When filename is a non-full path directory, it will prefix the filename with Manager Path instead of current directory.
• classmethod CopyDir(pSource As %String, pTarget As %String, pOverlay As %Boolean = 0, ByRef pCreated=0, pDeleteBeforeCopy As %Boolean = 0) as %Boolean
Copy a host directory from pSource to pTarget.
Parameter pOverlay Parameter pDeleteBeforeCopy may be used to specify that any file that already exists in the target directory should be deleted before being overwritten with the source file. The default is 0 or false.
This method returns true if it succeeds and false otherwise.
Note: (1) If the target directory exists and pOverlay is false (default), then the operation fails. Also, if any of the target files exist and pDeleteBeforeCopy is false (default), then the operation may fail usually due to operating system characteristics. (2) The total number of files or directories created/copied during the operation can be gotten by passing a byref value in pCreated.
• classmethod CopyFile(from As %String, to As %String, pDeleteBeforeCopy As %Boolean = 0, Output return As %Integer) as %Boolean
Copy a host file from to host file to.
Parameter pDeleteBeforeCopy may be used to specify that if the target file already exists then it should be deleted before being overwritten with the source file. The default is 0 or false.
This method returns true if it succeeds and false otherwise. Pass return by reference to obtain the low level return value in case of errors
• method CopyFromAndSave(source As %AbstractStream) as %Status
Method not implemented as it does not make sense in context of %File interface
• classmethod CreateDirectory(name As %String, Output return As %Integer) as %Boolean
Creates a directory with name name. Returns true if it succeeds and false otherwise. Pass return by reference to obtain the low level return value in case of errors
• classmethod CreateDirectoryChain(name As %String, Output return As %Integer) as %Boolean
Create this directory and all the parent directories if they do not exist. This differs from CreateDirectory as that method only creates one new directory where as this will create the entire chain of directories. Returns true if it succeeds and false otherwise. Pass return by reference to obtain the low level return value in case of errors
• classmethod CreateNewDir(directory As %String, name As %String, Output return As %Integer) as %Boolean
Given a directory name and the name of a new directory create this directory inside the given directory. Return true if it succeeds and false otherwise. Pass return by reference to obtain the low level return value in case of errors
• method DateCreatedGet() as %Date
This is a Get accessor method for the DateCreated property.
• method DateModifiedGet() as %Date
This is a Get accessor method for the DateModified property.
• classmethod Delete(filename As %String, Output return As %Integer) as %Integer
Deletes the file filename. Returns true if it succeeds and false otherwise. Pass return by reference to obtain the low level return value in case of errors
• classmethod DirectoryExists(filename As %String) as %Boolean
Tests if filename is a directory. returns 1 if it is a directory, otherwise, returns 0.
• classmethod DriveListClose(QHandle As %Binary) as %Status
• classmethod DriveListExecute(ByRef QHandle As %Binary, fullyqualified As %Boolean = 0) as %Status
• classmethod DriveListFetch(ByRef QHandle As %Binary, ByRef Row As %List, ByRef AtEnd As %Integer = 0) as %Status
• classmethod Exists(filename As %String, Output return As %Integer) as %Boolean
Returns true (1) if filename exists. Pass return by reference to obtain the low level return value in case of errors
• classmethod FileSetClose(QHandle As %Binary) as %Status
• classmethod FileSetExecute(ByRef QHandle As %Binary, directory As %String, wildcards As %String, sortby As %String = "", includedirs As %Boolean = 0, delimiter As %String = ";") as %Status
• classmethod FileSetFetch(ByRef QHandle As %Binary, ByRef Row As %List, ByRef AtEnd As %Integer = 0) as %Status
• classmethod GetDirectory(name As %String, keepterm As %Boolean = 0) as %String
Given a full directory and filename this will return just the directory portion of this name. This is useful as the parsing of filenames on Unix/Windows/VMS is different.
• classmethod GetDirectoryLength(name As %String) as %Integer
Return the number of pieces in this directory name
• classmethod GetDirectoryPiece(name As %String, piece As %Integer, ByRef fullpath As %String, ByRef IsDrive As %Boolean) as %String
Return the piece of a directory name
• classmethod GetDirectorySpace(Name As %String, ByRef FreeSpace As %String, ByRef TotalSpace As %String, Flag As %Integer = 1) as %Status
Return the amount of total space and free space in either Bytes,MB,GB on a drive or directory
Name = Valid Drive or directory specification
Flag = 0 - Return bytes
Flag = 1 - Return MB (Default)
Flag = 2 - Return GB

MB and GB returned are rounded to 2 decimal places.
Any error status returned is O/S level error. Note that on Windows only drives have a measurement for free space and directories can not so the FreeSpace is only returned for drives.
• classmethod GetFileDateCreated(filename As %String, utc As %Boolean = 0) as %String
Return the date created of file filename in $H format. By default this is local time, if you pass utc as true it returns it in UTC time. The value is rounded to second precision.
• classmethod GetFileDateModified(filename As %String, utc As %Boolean = 0) as %String
Return the date last modified of file filename in $H format. By default this is local time, if you pass utc as true it returns it in UTC time. The value is rounded to second precision.
• classmethod GetFileSize(filename As %String) as %Integer
Return the size of file filename in bytes.
• classmethod GetFilename(name As %String) as %String
Given a full directory and filename this will return just the filename portion of this name. This is useful as the parsing of filenames on Unix/Windows/VMS is different.
• method LastModifiedGet() as %TimeStamp
This is a Get accessor method for the LastModified property.
• classmethod ManagerDirectory() as %String
Returns the path of the Caché manager directory.
• classmethod NormalizeDirectory(filename As %String, directory As %String = "", addnull As %Boolean) as %String
Returns the normalized form of the directory name filename. If you pass directory then it will normalize this filename relative to the provided directory, if no directory is supplied then it is relative to the current default directory. addnull is set to true on VMS if normalizing the directory involves adding [000000] the the name
• classmethod NormalizeFilename(filename As %String, directory As %String = "") as %String
Returns the normalized form of the filename. If you pass directory then it will normalize this filename relative to the provided directory, if no directory is supplied then it is relative to the current default directory. If the directory does not exist then this method will return the empty string. Otherwise, this method returns the normalized full path name of the specified file.
• classmethod NormalizeFilenameWithSpaces(pathname As %String) as %String
Normalize filenames containing spaces for the host platform.

Parameter
pathname : A filename or pathname, specified as a quoted string. You cannot supply a Windows pathname as a doubly-quoted string.

Description
The NormalizeFilenameWithSpaces class method handles spaces in pathnames as appropriate to the host platform. If the pathname contains a space character, pathname handling is platform-dependent.

OpenVMS permits space characters in pathnames; NormalizeFilenameWithSpaces performs no special processing and returns the pathname unchanged.

UNIX only permits space characters in quoted pathnames; if a pathname containing spaces NormalizeFilenameWithSpaces returns the pathname enclosed in double quotes ("pathname"). If a pathname does not contain spaces, the method returns it unchanged. NormalizeFilenameWithSpaces performs no other pathname validation.

On Windows systems, NormalizeFilenameWithSpaces strips spaces from the supplied pathname of an existing file. If a pathname does not contain spaces, the method returns it unchanged in all cases. On Windows systems, the method validates pathnames that contain spaces. If a pathname containing spaces does not exist, NormalizeFilenameWithSpaces returns the pathname unchanged (with its blank spaces), with the entire pathname enclosed in double quotes ("pathname"). If a pathname containing spaces exists, the method returns the short form pathname with spaces removed, such as the following:
	WRITE ##class(%File).NormalizeFilenameWithSpaces("C:\My Test File.txt")
	C:\MYTEST~1.TXT
In this case, the filename is truncated to the first six non-blank characters, and a tilde (~) and an ordinal number are appending to distinguish similarly named files. For further details on Windows handling of pathname characters, specify cmd /? at the Windows command prompt.

NormalizefilenameWithSpaces is commonly used with the $ZF(-1) and $ZF(-2) functions.
• method Open(mode As %String = "", timeout As %Integer = 0) as %Status
Open the current file with mode mode.

mode is a string containing one or more file modes including:
RRead
WWrite
SStream mode
NCreate a new file (overwrite existing file)
Note that if the mode contains ':' characters this is a delimiter. For example if the mode="RN:/SHARED" then it will open the file with the equivalent of the COS command 'Open name:("RN":/SHARED):0'. The first piece before the ':' is quoted and the subsequent pieces are not.

A complete discussion of the available options for mode can be found in the online documentation in the book, Caché I/O Devices Guide, specifically the chapter on Sequential File I/O.

• classmethod ParentDirectoryName(directory As %String) as %String
Given a directory name, return the name of its parent directory.
If the directory is already the root (e.g., "/" on Unix, "c:\" on Windows or "dka1:" on VMS), return the root.
• classmethod ParseDirectoryClose(ByRef QHandle As %Binary) as %Status
• classmethod ParseDirectoryExecute(ByRef QHandle As %Binary, directory As %String) as %Status
• classmethod ParseDirectoryFetch(ByRef QHandle As %Binary, ByRef Row As %List, ByRef AtEnd As %Integer = 0) as %Status
• method Read(ByRef len As %Integer = 32000, ByRef sc As %Status) as %CacheString
Read up to len characters from this File.
• classmethod ReadOnly(filename As %String) as %Integer
Return true if the file is read only and false if it is writable
• classmethod RemoveDirectory(name As %String, Output return As %Integer) as %Integer
Removes directory name. Returns true if it succeeds and false otherwise. Pass return by reference to obtain the low level return value in case of errors
• classmethod RemoveDirectoryTree(pTarget As %String) as %Integer
Recursively remove directory pTarget. Returns true if it succeeds and false otherwise.
• classmethod Rename(oldname As %String, newname As %String, Output return As %Integer) as %Integer
Rename file oldname to newname. Returns true if it succeeds and false otherwise. The rename subfunction is only intended for changing the name of a regular file, not directories or other types of files. In particular, renaming a file across filesystems results in copying and deleting the original file, but this will not work for a directory. Renaming a directory within a file system does work. Pass return by reference to obtain the low level return value in case of errors
• method Rewind() as %Status
Moves the current location to the beginning of the stream.
• classmethod SHA1Hash(file As %String, type As %Integer = 0) as %String
Return binary form of SHA1 hash on the file if type is 0 (the default). If you want the string version then pass in type as 1. Note that if you already have the file open in this process calling this function will close this file.
• classmethod SetAttributes(filename As %String, attributes As %String, Output return As %Integer) as %Boolean
Set the OS specific attributes of the file. See the Attribute method in this class for file attribute values. Pass return by reference to obtain the low level return value in case of errors
• classmethod SetReadOnly(filename As %String, leaveexisting As %Boolean = 0, Output return As %Integer) as %Boolean
Make this file/directory read only (if we can). If leaveexisting is true then it will add read permissions to the file/directory without changing the existing permissions, by default it will remove all other permissions other than read only flags. The leaveexisting has no effect on Windows so you do not need to pass this argument on this platform. Pass return by reference to obtain the low level return value in case of errors
• classmethod SetUMask(NewMask As %Integer) as %Integer
Set umask to the given value and return the previous umask value
• classmethod SetWriteable(filename As %String, writeonly As %Boolean = 1, Output return As %Integer) as %Boolean
Make this file/directory writable (if we can). The writeonly defaults to true in which case this makes the file write only, if you just want to add writable to the existing permissions without modifying the other permissions pass writeonly=0. The writeonly has no effect on Windows so you do not need to pass this argument on this platform. Pass return by reference to obtain the low level return value in case of errors
• method SizeGet() as %Integer
This is a Get accessor method for the Size property.
• classmethod SubDirectoryName(directory As %String, name As %String, normalized As %Boolean = 0) as %String
Given a directory name and the name of a sub directory create the name for the subdirectory inside the given directory. Return the new directory name. This is useful as the parsing of filenames on Unix/Windows/VMS is different.
• classmethod TempFilename(ext As %String = "tmp") as %String
Return a temporary filename in the temp directory. If you specify ext the temp filename will have this extension else it will default to 'tmp'.
• classmethod VMSRecordFormat(filename As %String) as %String
Return information on the VMS record format for this file. This function only works on VMS and returns one of returns one of the following strings: "UDF", "FIX", "VAR", "VFC", "STM", "STMLF", "STMCR". This allows a user to determine what OPEN mode should be used to read an unknown file from Cache.
• method Write(data As %CacheString = "") as %Status
Write data to this %File object.
• method WriteLine(data As %CacheString = "") as %Status
Write data with a carriage return to this %File object.
• classmethod Writeable(filename As %String) as %Boolean
Return true if the file/directory is writable and false if it is not

Queries

• query DriveList(fullyqualified As %Boolean = 0)
Selects Drive As %String
This query was originally created to return Windows drive letters, hence its name. Later it was extended to work on VMS and Unix.
  • Windows: return a list of available drives
  • Unix: return a list of mounted file systems
  • VMS: return a list of available disk devices
On Windows, if fullyqualified is true then the drive letters include the trailing '\' character. The default is false; this is backward compatible and returns 'c:' on Windows. This does not affect the behavior on VMS or Unix.
• query FileSet(directory As %String(MAXLEN=""), wildcards As %String, sortby As %String = "", includedirs As %Boolean = 0, delimiter As %String = ";")
Selects Name As %String, Type As %String, Size As %BigInt, DateCreated As %TimeStamp, DateModified As %TimeStamp, ItemName As %String
Return the list of files in directory matching the pattern wildcards. The sortby can be one of:
  • Name - the name of the file (the default)
  • Type - file type
  • DateCreated - the date the file was created (rounded to second)
  • DateModified - the date the file was last modified (rounded to second)
  • Size - the file size
The includedirs if true (default is 0) will force the list of all directories to be returned before any files, the directories will ignore the pattern you supplied so it returns them all. If it is false it will return any files that match the pattern you give it, this may include directories if they match the pattern as well. So true forces any directory to be included, but false does not exclude directories. You may also specify the delimiter that is used to separate the wildcards from each other, this defaults to ";".
• query ParseDirectory(directory As %String(MAXLEN=""))
Selects Name As %String, IsDrive As %Boolean, Directory As %String
Given a directory name return it pulled apart into individual subdirectories starting at the root node and working down to the last directory name


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