C, Getting segmentation fault -

i have file called islands.txt contents:

islandone islandtwo islandthree 

and code:

#include <stdio.h> #include <stdlib.h> #include <string.h>  typedef struct island{     char *name;     struct island *previous; } island;  void printisland(island is){     printf("%s", is.name);     if(is.previous && is.previous->name[0] != '\0'){         printf("%s", is.previous->name);     } }  int main(){      // file read.     file *islandsfile = fopen("islands.txt","r");      // temporary location store name read file.     char name[40];      // temporary pointer island has been read linking.     island *previousisland;      while(fscanf(islandsfile,"%s",name) != eof){         // allocate space new island , point (*newisland) pointer         island *newisland =malloc(sizeof(island));          // assign name         newisland->name = name;          // if previousisland pointer not null         // means there island read before newisland in file          if(previousisland){             // newisland.previous should hold address of read island..             newisland->previous = previousisland;         }         // previousisland newisland..         previousisland = newisland;         printisland(*newisland);         puts("");     }      fclose(islandsfile); } 

my expectation of output is:

islandone islandtwoislandone islandthreeislandtwo 

instead getting segmentation fault. have tried stuck. getting segmentation fault here? pretty new c , have no idea how debug.

yes need allocate memory name well. allocate structure

typedef struct island{     char *name;     struct island *previous; } island; 

so this

// assign name newisland->name = name; 

will set pointer array have on stack, every loop iteration same address.

instead like

newisland->name = strdup(name); 

or if prefer

newisland->name = malloc( strlen( name ) + 1 ); strcpy( newisland->name, name );