Chapter 6 Function Descriptions
FIsARefNum
Bool32FIsARefNum(refNum);
Purpose
Determines whether refNum is a valid file refnum.
Parameters
Name |
Type |
Description |
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refNum |
LVRefNum |
File refnum you want to verify. |
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Return Value
Bool32, which can contain the following values:
TRUE |
File refnum has been created and not yet disposed. |
FALSE |
File refnum is not valid. |
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Chapter 6 Function Descriptions
FIsEmptyPath
Bool32 FIsEmptyPath(path);
Purpose
Determines whether path is a valid empty path.
Parameters
Name |
Type |
Description |
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path |
Path |
Path you want to verify. |
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Return Value
Bool32, which can contain the following values:
TRUE |
Path is well formed and empty and type is absolute or relative. |
FALSE |
Path is not a valid empty path. |
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Chapter 6 Function Descriptions
FListDir
MgErr FListDir(path, list, typeH);
Purpose
Determines the contents of a directory.
The function fills the AZ handle passed in list with a CPStr, where the cnt field specifies the number of concatenated Pascal strings that follow in the str[] field. Refer to the Basic Data Types section in Chapter 4, Programming Issues for CINs, for a description of the CPStr data type. If typeH is not NULL, the function fills the AZ handle passed in typeH with the file type information for each file name or directory name stored in list.
Parameters
Name |
Type |
Description |
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path |
Path |
Path of the directory whose contents you |
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want to determine. |
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list |
CPStrHandle |
Application zone handle in which FListDir |
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stores a series of concatenated Pascal strings, |
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preceded by a 4-byte integer field, cnt, that |
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indicates the number of items in the buffer. |
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typeH |
FileType |
Application zone handle in which FListDir |
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stores a series of FileType records. If |
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typeH is not NULL, FListDir stores one |
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FileType record in typeH for each Pascal |
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string in list. The nth FileType in typeH |
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denotes the file type information about the |
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file or directory named in the nth string in list. |
The file type record is:
typedef struct {
int32 flags;
int32 type;
} FileType;
Only the least significant four bits of flags contain useful information. The remaining bits are reserved for use by LabVIEW. You can test these four bits using the following four masks:
#define kIsFile 0x01
#define kRecognizedType 0x02
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Chapter 6 Function Descriptions
#define kIsLink 0x04
#define kFIsInvisible 0x08
The kIsFile bit is set if the item described by the file type record is a file; otherwise, it is clear. The kRecognizedType bit is set if the item described is a file for which you can determine a 4-character file type; otherwise, it is clear. The kIsLink bit is set if the item described is a UNIX link or Macintosh alias; otherwise, it is clear. The kFIsInvisible bit is set if the item described does not appear in a file dialog; otherwise, it is clear.
The value of type is defined only if the kRecognizedType bit is set in flags. In this case, type is the 4-character file type of the file described by the file type record. This 4-character file type is provided by the file system in Macintosh and is computed by examining the file name extension on other systems.
Return Value
mgErr, which can contain the following errors: mgArgErr
FNotFound
FNoPerm
MFullErr fIOErr
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