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soFromCurrent

soFromCurrent = 1

Example​

function SkipBytes(Stream: TStream; Count: Int64): Int64;
begin
  Result := Stream.Seek(Count, soFromCurrent);
end;

Usage​

soFromCurrent makes TStream.Seek add a signed Int64 offset to the stream's current shared byte cursor.

Additional Technical Info​

soFromCurrent makes TStream.Seek move relative to the live cursor: new position = current position + Offset. A positive offset moves forward, zero queries/retains the position through the seek dispatch, and a negative offset moves backward when the descendant permits the result.

The constant is the legacy LongInt ordinal 1. Velox's current script method accepts Origin: Word and an Int64 offset; Delphi maps ordinal 1 to typed soCurrent before virtual descendant behavior runs.

State and error behavior

  • Repeated calls accumulate. Reads, writes and other consumers also advance the same cursor, so a relative operation depends on all preceding stream activity.
  • A negative move before byte 0 is invalid for ordinary file/memory streams. A positive move beyond Size may be allowed without extending the stream until a write occurs.
  • The operation is unsynchronised. Do not use relative seeking while another consumer can read, write or seek the same instance.
  • The Int64 return is the resulting absolute position and is safer than the narrowed script Position property for large streams.

The constant does not imply that every TStream descendant is seekable. Unsupported descendants can raise or otherwise reject the operation.

The example is source-reviewed only; no stream cursor was moved.

External references

Created 2026-07-15