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IndexByte function

In unit System

Search for a byte in a memory range.

Declaration

pascal
function IndexByte(const buf; len: SizeInt; b: Byte): SizeInt

Description

IndexByte searches the memory at buf for maximally len positions for the byte b and returns it's position if it found one. If b is not found then -1 is returned. The position is zero-based.

Errors

Buf and Len are not checked to see if they are valid values.

See also

Example: ex105

pascal
Program Example105;

{ Program to demonstrate the IndexByte function. }

Const
  ArraySize = 256;
  MaxValue = 256;

Var
  Buffer : Array[1..ArraySize] of Byte;
  I,J : longint;
  K : Byte;

begin
  Randomize;
  For I:=1 To ArraySize do
    Buffer[I]:=Random(MaxValue);
  For I:=1 to 10 do
    begin
    K:=Random(MaxValue);
    J:=IndexByte(Buffer,ArraySize,K);
    if J=-1 then
      Writeln('Value ',K,' was not found in buffer.')
    else
      Writeln('Found ',K,' at position ',J,' in buffer');
    end;
end.

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.