Most efficient way to build a big variable length string?

[mdijkens]

I need to build a huge variable length string (>1GB) in memory before calling a function or writing to a file.
I already found out I can most efficiently build it up in a _MEM block.
But what is the best way to move that in the end to a variable string without copying and doubling the memory used.
So basically I am looking to a more efficient way to do:

Code: (Select All)

sql$ = Space$(mpos): _MemGet m, m.OFFSET, sql$

for very big mpos?
Is that even possible?

related to this, what is the most efficient coding to work with a big string where you have to remove a lot of pieces out without doing something like:

Code: (Select All)

sql$ = Left$(sql$, mpos - 1) + Mid$(sql$, mpos + 1)

With very big strings this is also expensive