我怎么知道fgets读取的单词是否在新行中？

Question

I'm reading a program in C and I want to locate the new line, but i don't know how.

I'm reading the text file like this:

    while(!feof(fp)){
         fgets(buffer, 4, fp);
    }

and my text file is like this:

C01 RDA ALB NAC EDF
C02 MCA EDF SLF ADG

how would I know if the word being read by fgets is in a new line??

Answer 1

You're not supposed to call feof() before doing I/O, that's simply not how it works.

If you're that interested in the location of each newline, read the file character by character instead, using fgetc() . Then parse the character stream into words. This will make it trivial to notice when a newline comes along.

Answer 2

Do you really want to get three characters at a time (which is what you get for size 4, because fgets reads one less than size characters), thus getting the pieces

C01 RD A A LB NAC ED F¶ C02 MC A E DF SLF AD G¶

( ¶ denoting newline)? I don't think so, but rather you want four characters at a time and trim the word delimiters.

char buffer[5];
char newline = 1;
while (fgets(buffer, sizeof buffer, fp))
{
    if (newline) puts("new line:");
    newline = buffer[3] == '\n';
    buffer[3] = '\0';
    puts(buffer);
}