I am trying to copy a string to an array of string. I have used these two examples before and they have worked so I don't understand why they won't work this time. I am getting a segmentation fault.


I remembered to initialize everything.

char *strings_mneumonic_table[503] = {0};
char mneumonic[20] = {0};
int start_address = 0;
int hash = 0;
        if(line[0] == 32)
            printf("32 group \n");
            sscanf(line, "%s %x", mneumonic ,&start_address);
            printf("mneumonic is %s\n", mneumonic);
            printf(" hash is %d \n", hash);
            strcpy(strings_mneumonic_table[hash], mneumonic);
            //printf("under strcpy(strings_mneumonic_table[hash], mneumonic); \n");
            //hex_address_table[hash] = start_address;
            //printf("hex_address_table[hash] = start_address; \n");
            //printf("end of 32 group \n");

Here is my output

hash is 2 
little start 
32 group 
mneumonic is START
hash is 2 
Segmentation fault (core dumped)

Could you elaborate on that please? I thought those are 2 separate things. I thought the first one is declaring a char pointer to stdup. I thought the second one is const char pointer to source where you can't change it (which I need to add values to it as I run my program) and you can make a string a string array that can't change.

char* strdup
const char* source

These are your 2 choices that I am familiar with. I like the first one because its more efficient. Since I'm using C I like to be efficient :).

strs[i] = malloc(strlen("foo") + 1);
strcpy(strs[i], "foo");


Edited 2 Years Ago by COKEDUDE

Rubberman was suggesting that you use the strdup function found in string.h.
In his post he posted the definition of the function as found in the header:
char* strdup(const char* source);
In other words strdup is a function which takes a const char* as a parameter and returns a char*.
You would use it in code like this:
char* copy = strdup(originalString);
Where originalString is the char* that you want to create a copy of.
The strdup function will create a duplicate of the string and returns a pointer to the copied string. So the variable "copy" will point to the copy of originalString.

You are using strdup as a variable. It is also the name of a C-function that copies a string. Better to do this:

        const char* source = "foo";
        char *strs[NUMBER_OF_STRINGS][STRING_LENGTH+1];
        strs[i] = strdup(source);
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