c - Segmentation faults while opening file -

i'm getting confused right now. want create file , write string created before. when following code gets executed there happens segmentation fault error , program terminates.

file* output; output = fopen("test.txt", "w"); fprintf(output, line); fclose(output); 

the line declared following.

char* line = null; line = malloc(1048576 + 1); 

first i've considered error appears because of malloc, code isn't working either:

file* output; output = fopen("test.txt", "w"); fprintf(output, "lbasdhasd"); fclose(output); 

what doing wrong? in code runs before lines i've used file pointer file closed.

your code bad not check errors. output null pointer (and one):

#include <errno.h> #include <string.h>  file* output; output = fopen("test.txt", "w"); if(!output){    //handle error    printf("something went wrong: %s", strerror(errno));    exit(1); } fprintf(output, "lbasdhasd"); fclose(output); 

are sure have permission create file in cwd?

fopen() sets errno error code in case of failure. usual strerror(errno) give description of error code.