如何在C中一起使用getline和strtok？

Question

this is my first time asking a question here so I hope I am doing it correctly! For a while now I have been trying to get getline and strtok to work together in order to read text from a file and break it into words. Essentially the text file input is an essay and I want to manipulate each word individually later on. The problem I am getting is a constant "assignment makes pointer from integer without a cast"; I have tried everything I can think of. This is my code as of right now:

int nbytes = 100;
char *buffer;
char *token;
buffer = (char *) malloc(nbytes + 1);
getline(&buffer,&nbytes,file);
token = strtok(&buffer, " ");

I feel like it's problem something really simple that I am overlooking. That you for reading and your help!

Answer 1

Standard C (on its own) doesn't define anything named getline . To read a line from a file you normally use fgets .

The error you describe sounds like you don't have a prototype for strtok in scope, so the compiler is treating it as if it returned the default type (int). You'd normally eliminate that by adding #include <string.h> somewhere close to the top of the file.

Answer 2

I don't think you want &buffer in your strtok() call. Also, you're not including string.h , which is why you're getting the warning "assignment makes pointer from integer without a cast". Without a correct prototype for strtok() available, the compiler is assuming that it returns int . The conversion of that int to char * to make the assignment to token is the assignment it's complaining about.

Edit - thanks to @dmckee for the signature of getline() .

Answer 3

one more error is using &buffer instead of buffer.

&buffer is pointer to pointer to char, but you need pointer to char.