c - Sending structure through pipe without losing data -

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i have structure:

typedef struct {     int pid;     char arg[100];     int nr; } str;

the code this:

int main() {     int c2p[2];     pipe(c2p);     int f = fork();      if (f == 0) { // child         str s;         s.pid = 1234;         strcpy(s.arg, "abcdef");         s.nr = 1;          close(c2p[0]);         write(c2p[1], &s, sizeof(str*));         close(c2p[1]);         exit(0);     }      // parent     wait(0);     close(c2p[1]);     str s;     read(c2p[0], &s, sizeof(str*));     printf("pid: %d nr: %d arg: %s", s.pid, s.nr, s.arg);     close(c2p[0]);     return 0; }

the output this:

pid: 1234 nr: 0 arg: abc$%^&

pid right, nr 0 , fist few characters arg right followed random characters.

i want create structure in child process , send structure parent process through pipe.

how can send correctly structure through pipe?

write(c2p[1], &s, sizeof(str*));

is not right. write number of bytes size of pointer. should be

write(c2p[1], &s, sizeof(str)); // -- without `*`.

similarly, need use:

read(c2p[0], &s, sizeof(str));  // -- without `*`.

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