FileSeek

Description

This function block sets the current position in an open file.

Figure 7-213: The FileCopy Function Block

Related Functions

FileClose, FileEOF, FileOpenA, FileOpenR, FileOpenW, FileReadLine, FileReadBinData, FileWriteBinData, FileWriteLine

See also: File Management

Arguments

Input

Execute	Description	On the rising edge A rising edge is the transition of a digital signal from low to high. It is also called positive edge test if the end of the file is reached in a file that is open for reading.
	Data Type	BOOL
	Range	0, 1
	Unit	N/A
	Default	—
ID	Description	ID of the open file.
	Data Type	UDINT
	Range	N/A
	Unit	N/A
	Default	—
POS	Description	Number of bytes to offset from ORG. If ORG = SEEK_SET, then POS should be ≥ 0 If ORG = SEEK_END, then POS should be ≤ 0 If ORG = SEEK_CUR, then POS can be positive or negative
	Data Type	DINT
	Range	N/A
	Unit	N/A
	Default	—
ORG	Description	Origin of the move. SEEK_SET = beginning of the file SEEK_CUR = current position SEEK_END = end of the file
	Data Type	DINT
	Range	SEEK_SET, SEEK_CUR, SEEK_END
	Unit	N/A
	Default	—

Output

Done	Description	If TRUE, then the command completed successfully
	Data Type	BOOL
Error	Description	If TRUE, an error has occurred
	Data Type	BOOL
ErrorID	Description	Indicates the error if Error output is set to TRUE. See the table in Search IndexFile and TCP/IP Function Block ErrorID Output
	Data Type	DINT

Example

Structured Text

(* FileSeek example *)
CASE StepCounter OF
0:
   (* Move to beginning of the file *)
   Inst_FileSeek(TRUE, MyInputFileID, 0, SEEK_SET);
   StepCounter := StepCounter + 1;
1:
   Inst_FileSeek(TRUE, MyInputFileID, 0, SEEK_SET);
   IF Inst_FileSeek.Done THEN
      Inst_FileSeek(FALSE, 0, 0, SEEK_SET);
      StepCounter := StepCounter + 1;
   END_IF;
END_CASE;