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cinitializationstructurevalgrind

Uninitialized Condition Valgrind

After running the following C program with Valgrind, it says the packets.payload variable is uninitialised. But I cannot figure out why since I've already put "1234567890" in packets.payload

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

typedef struct packet {
    int payload_length;
    char payload[10];
} packet_t;


int main () {
    packet_t packet;
    strncpy(packet.payload, "1234567890", 10);
    puts(packet.payload);
}
Solution

  • A pointer to a string (a sequence of characters terminated by null-character) must be passed to puts().

    Your packet.payload doesn't contain terminating null-character, so you cannot use it for puts().

    You can use printf() with specifying length to print to print that:

    printf("%.*s\n", 10, packet.payload);