Locking files

[sripriyaunni]

Can anyone tell me about the locks that I can put in files accessed using OPEN method? What is the difference between LOCK READ,LOCK WRITE,LOCK READ WRITE and SHARED?

[Cimperiali]

Lock read = other processes (other programs) cannot read the file
Lock write = other cannot write to file (but can read it)
Shared= other can read or write the file
lock read Write = other cannot open the file for reading or for writing

Here a couple of example from MSDN


This code example opens the file in Binary mode for reading; other processes can't read file.
Open "TESTFILE" For Binary Access Read Lock Read As #1

This code example opens the file for sequential output; any process can read or write to file.
Open "TESTFILE" For Output Shared As #1
' Close before reopening in another mode.
Close #1




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