Recognizing EOF vs newline in getline in C

Question

is there any way how to recognize if getline was ended because of newline or because of EOF?
So, I would like to distinguish:
1.
alfa n beta n gama n EOF
2.
alfa n beta n gama EOF
In the second case I don't want to read gama as a new string and I want to say, that the reading of last string was not successful. I am using while cycle to read the lines.
I can't edit incoming data.
There is probably possibility to solve this by using getchar. However it makes reading lines more complicated :-/
Thank you so much

Jan Dunder · Answer

Thank you for your tips.
Finally I used easier way how to do it.
characters = getline(&line, &len, stream);
if (characters==-1) {puts("Input ended by EOF after n");}
if (feof(stdin)) {puts("Input ended by just EOF");}

chux - Reinstate Monica · Answer

is there any way how to recognize if getline was ended because of newline or because of EOF?

If the line input stopped due to end-of-file, feof() returns true.
ssize_t nread = getline(&line, &len, stream);
if (feof(stream)) {
  puts("Input ended due to end-of-file");
}
if (nread > 0 && line[nread-1] == 'n') {
  puts("Input ended due to end-of-line");
}

It is possible for both to be false: input error or allocation failure.

Concerning fgets(), additional issues occur when the buffer is full or a null character was read.

Shawn · Answer

Like fgets(), getline() includes the trailing newline in the string. So just check the last character after a successful call to see if it's a 'n'. If it's something else, you have the last line of a file without a trailing newline.

Recognizing EOF vs newline in getline in C

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