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Plc programming – Lenze ETC Motion Control User Manual

Page 386

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PLC programming

Library
FILE IO functions

8

8.8
8.8.3

l

386

EDSTCXN EN 2.0

8.8.3.7

SYSREADLINE

FUNCTION SYSREADLINE: DINT

VAR_INPUT

handle_di

: DINT;

(* File handle returned by SysOpenFile *)

buffer_p

: DINT;

(* Address of a buffer where the data are stored *)

maxlen_di

: DINT;

(* Buffer length in byte *)

END_VAR

The function is used for the reading of lines (in sequence) from a file
previously opened with SysOpenFile(). Reading takes place up to the line end
but with a maximum of maxlen_di characters. The is only terminated early
if less than maxlen_d characters were read. The line feed at the end of the
line is also read.

Return value: Actual number of read characters; 0 for file end or less than 0
for error (

391).

8.8.3.8

SYSWRITEFILE

FUNCTION SYSWRITEFILE: DINT

VAR_INPUT

handle_di

: DINT;

(* File handle returned by SysOpenFile *)

buffer_p

: DINT;

(* Address of a uffer *)

len_di

: DINT;

(* number of the characters to be written *)

END_VAR

The function is used to write blocks (in sequence) into a file previously
opened with SysOpenFile(). len_di characters will be written to the file. If an
error occurs during write, the file will be deleted and a value of less than 0
returend.

Return value: Number of data written, or less than 0 in case of error (

391).

handle_di

: DINT;

num_di

: DINT;

ret_di

: DINT;

buffer_s

: STRING(10) := ’Hello’;

handle_di

:= SYSOPENFILE(’test.dat’, O_WRONLY);

num_di

:= SYSWRITEFILE(handle_di, ADR(buffer_s), 5);

ret_di

:= SYSCLOSEFILE(handle_di);

Declaration

Description

Declaration

Description

Example