FindString for memory block

[UserOfPure]

Would be GREAT if there was a command to find a string in a memory block (perhaps called "FindStringInMemory"?), with the result being the offset from the start of the memory block. It would work just like FindString but without dying when it finds a 0-byte.

So if my memory block looked like this (hex bytes shown):

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41 42 43 00 44 45 46 00 47 48 49 ; ABC DEF GHI

Then the following command would return 5 because "DEF" is at offset 5:

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Debug FindStringInMemory(memory,"DEF",1)

[Demivec]

Would be GREAT if there was a command to find a string in a memory block (perhaps called "FindStringInMemory"?), with the result being the offset from the start of the memory block. It would work just like FindString but without dying when it finds a 0-byte.

So if my memory block looked like this (hex bytes shown):

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41 42 43 00 44 45 46 00 47 48 49 ; ABC DEF GHI

Then the following command would return 5 because "DEF" is at offset 5:

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Debug FindStringInMemory(memory,"DEF",1)

How would the command know when to stop searching if it continued past a 0-byte? Wouldn't that cause IMA's each time the string was not found?

[UserOfPure]

How would the command know when to stop searching

Since every allocated memory block has a set size, then obviously the search stops at the end of it. An optional "length" parameter could be used, too.

[Trond]

You can code this in just 8 lines:

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Procedure FindStringInMemory(String.s, Memory, MemoryLength)
  Protected L = Len(String)
  For I = 0 To MemoryLength-L
    If CompareMemory(@String, Memory+I, L)
      ProcedureReturn I+1
    EndIf
  Next
EndProcedure

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Memory.s = "ABC DEF GHI"

Debug FindStringInMemory("DEF", @Memory, Len(Memory))

[gnozal]

Some alternatives (QuickSearch ...) here : http://www.purebasic.fr/english/viewtop ... 12&t=27908

[UserOfPure]

Trond, but is that just for searching the memory of strings? I want to search a memory block that was created with AllocateMemory, which has 0 bytes in it where the required text to find is.

gnozal, thanks for the link, but I already have a custom routine written to do the job, but it's slow and I know a native command by Fred and Co would be 100% faster and more efficient.

[Trond]

Trond, but is that just for searching the memory of strings?

All memory are equally good memory. It really doesn't matter whether your memory area is part of a string or not. I just used a string in the example. The first parameter is always a string, which is what you asked for.