C Function to add line in a file

C Function to add line in a file

int add_line(char *cfg_cmd)
{
int ret=-1;

FILE *fp;

fp = fopen("test.txt", "a+");
if(fp != NULL)
{
fprintf(fp,"%s",cfg_cmd);
fclose(fp);
ret = 0;
}
else
{
ret = -1;
fclose(fp);

}

return ret;
}