linux c 获取文件行数

源代码如下：

/*获取文件行数*/
int file_wc(const char *filename)
{
        int fd;
        register int linect = 0;
        char buf[MAXBSTZE];
        int len;
        char *p = NULL;
        if(filename) {
                if((fd = open(filename, O_RDONLY)) < 0) {
                        fprintf(stderr, "open %s\n",strerror(errno));
                        return -1;
                }

                while(1) {
                        if((len = read(fd,buf,MAXBSTZE)) == -1) {
                            return -1;
                        }
                        if(len == 0){
                            break;
                        }
                        for( p = buf; len--; ){
                            if( *p == ‘\n‘ ){
                               ++linect;
                            }
                            ++p;
                        }
                }
        }

        return linect;

}

int main(){
    printf("%d\n",file_wc("a.txt"));
    return 0;
}