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Jamal
Jamal
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I created this small function just to practice C code. It's It's a simple random string generator.

I added the mySeedmySeed var so that if I call it twice with the same length it doesn't give me the same exact string.

Thanks

EDIT:EDIT:

Thanks for the improvements. II have changed the code to this:

I know that in the sizeof(charset)sizeof(charset) you don't have to use the ()(). You only need them when using sizeof with types, but it's just out of habit :D.

I created this small function just to practice C code. It's a simple random string generator.

I added the mySeed var so that if I call it twice with the same length it doesn't give me the same exact string.

Thanks

EDIT:

Thanks for the improvements. I have changed the code to this:

I know that in the sizeof(charset) you don't have to use the (). You only need them when using sizeof with types, but it's just out of habit :D

I created this small function just to practice C code. It's a simple random string generator.

I added the mySeed var so that if I call it twice with the same length it doesn't give me the same exact string.

EDIT:

I have changed the code to this:

I know that in the sizeof(charset) you don't have to use the (). You only need them when using sizeof with types, but it's just out of habit.

Added new version of the code
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AntonioCS
AntonioCS
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EDIT:

Thanks for the improvements. I have changed the code to this:

char *randstring(size_t length) {
    
    static char charset[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789,.-#'?!";        
    char *randomString = NULL;
    
    if (length) {
        randomString = malloc(sizeof(char) * (length +1));

        if (randomString) {            
            for (int n = 0;n < length;n++) {            
                int key = rand() % (int)(sizeof(charset) -1);
                randomString[n] = charset[key];
            }

            randomString[length] = '\0';
        }
    }
    
    return randomString;
}

I know that in the sizeof(charset) you don't have to use the (). You only need them when using sizeof with types, but it's just out of habit :D

EDIT:

Thanks for the improvements. I have changed the code to this:

char *randstring(size_t length) {
    
    static char charset[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789,.-#'?!";        
    char *randomString = NULL;
    
    if (length) {
        randomString = malloc(sizeof(char) * (length +1));

        if (randomString) {            
            for (int n = 0;n < length;n++) {            
                int key = rand() % (int)(sizeof(charset) -1);
                randomString[n] = charset[key];
            }

            randomString[length] = '\0';
        }
    }
    
    return randomString;
}

I know that in the sizeof(charset) you don't have to use the (). You only need them when using sizeof with types, but it's just out of habit :D

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AntonioCS
AntonioCS
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Random String generator in C

I created this small function just to practice C code. It's a simple random string generator.

#include <string.h>
#include <time.h>

char *randstring(int length) {    
    static int mySeed = 25011984;
    char *string = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789,.-#'?!";
    size_t stringLen = strlen(string);        
    char *randomString = NULL;
    
    srand(time(NULL) * length + ++mySeed);
    
    if (length < 1) {
        length = 1;
    }
    
    randomString = malloc(sizeof(char) * (length +1));
    
    if (randomString) {
        short key = 0;
        
        for (int n = 0;n < length;n++) {            
            key = rand() % stringLen;          
            randomString[n] = string[key];
        }
        
        randomString[length] = '\0';
            
        return randomString;        
    }
    else {
        printf("No memory");
        exit(1);
    }
}

The code seems to work ok. Any ideas, improvements or bugs?

I added the mySeed var so that if I call it twice with the same length it doesn't give me the same exact string.

Thanks