Provided by standard library.
DELETE removes a partial string from a larger string at a defined position.
The input variable STR is type STRING, LEN and POS are type INT, the return value of the function is type STRING.
DELETE(STR, L, P) means: Delete L characters from STR beginning with the character in the P position.
Example in Function Block Diagram
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Example in Structured Text
Var1 := DELETE ('SUXYSI',2,3);
String functions are not "thread safe": When using tasks, string functions may only be used in a single task. If the same function is used in different tasks, there is a danger of overwriting.