c - Arduino C - censoring variable data

Question

I have two variables:

• dataRx (SLAVE::1234)
• globalAuthcode (1234)

and I comparing

     if(strcmp(dataRx, globalAuthcode) == 0)

I can't find function like SUBSTR from PHP :) I want leve only 1234 from dataRx variable.

Answer 1

Use pointer arithmetics:

strcmp(dataRx + 7, globalAuthcode)
/*           ^^^^ */

The dataRx + 7 skips over the first seven characters of the string. Of course, you might want to make sure that the string is at least 7 characters before doing that.