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cfileargv

"Pointer from integer without cast" warning when opening file.

I have this homework to do in C. I'm beginner so it is probably very easy, but anyway I have a problem with it. 

int main(int argc, char* argv){

    int fd=open(argv[1], O_RDONLY);
    int fileLength=(int)lseek(fd,0,SEEK_END);
    lseek(fd,0,SEEK_SET);
    char buf[fileLength];
    read(fd,buf,fileLength);
    int i=0;
    for(i=0; i<fileLength; i++){
        printf("%c",buf[i]);
    }
    printf("\n");
}

I get this error:

warning: passing argument 1 of ‘open’ makes pointer from integer without a cast

If I write "file" instead of argv[1], everything is ok.

Solution 
  • int main(int argc, char* argv){

    has to be:

    int main(int argc, char *argv[])

    See the error?