C++ Rewrite a file but leaving out everything before a word

Question

I\'m using Visual C++ Express 2010... and I\'m very new to C++.

I want to read a file then remove everything before the word \"<--START-->\" and rewrite the file

Answer 1

Here's a version that doesn't have to read the whole file into memory. Note: uses C stdio, not iostreams (just because I know C stdio a lot better); reads from standard input, writes to standard output.

#include 

int
main(void)
{
    int c;
    enum { BOF, LT, D1, D2, S, T1, A, R, T2, D3, D4, GO } state = BOF;
    while ((c = getchar()) != EOF)
        switch (state)
        {
        case BOF: state = c == '<' ? LT : BOF; break;
        case LT:  state = c == '-' ? D1 : c == '<' ? LT : BOF; break;
        case D1:  state = c == '-' ? D2 : c == '<' ? LT : BOF; break;
        case D2:  state = c == 'S' ? S  : c == '<' ? LT : BOF; break;
        case S:   state = c == 'T' ? T1 : c == '<' ? LT : BOF; break;
        case T1:  state = c == 'A' ? A  : c == '<' ? LT : BOF; break;
        case A:   state = c == 'R' ? R  : c == '<' ? LT : BOF; break;
        case R:   state = c == 'T' ? T2 : c == '<' ? LT : BOF; break;
        case T2:  state = c == '-' ? D3 : c == '<' ? LT : BOF; break;
        case D3:  state = c == '-' ? D4 : c == '<' ? LT : BOF; break;
        case D4:  state = c == '>' ? GO : c == '<' ? LT : BOF; break;
        case GO:  putchar(c); break;
        }
    return 0;
}