After reading all the responses I realized there is no easy way....
My description is correct , it's a null-terminated ASCII string(one character one byte, no special ones), its length is not stored anywhere. Using static array only fixes problem of missing a first byte....
What I wanted to avoid the most is reading the string byte by byte until #0 is found.
I'll try this way.
Perhaps but the file I want to read was created in Visual Studio ..so I presume in C++ are "normal" ways to read #0 strings.