hey
i have a small problem related to char pointers.

i have to concatenate two strings. str1 and ".part".
but i do not no the size of str1.str1 is to be given by the user.
so when i use *str1 to store wat user entered and try to concatenate using strcat() i get error saying segmentation fault....

plz help

Without knowing which functions you're exactly using:

The user input is probably not a null terminated string, so you must make sure it's null terminated. Easiest is probably to zero the buffer before putting data in it; check man memset.

If you allocate a buffer for userinput, you must prevent the user to entering more data or limit whatever has been read. Check man fgets for reading userinput and limiting the amount of characters.

There is a dedicated programming section at LQ

PS Another point: if you declared a char *str1, this is only a pointer. You need to allocate memory before you can use it; a function that you use might already do that but without seeing the code it's difficult to say.

hey thnks a lot for a quick reply.......