From mboxrd@z Thu Jan  1 00:00:00 1970
From: dhog@plan9.bell-labs.com
Message-Id: <200006161950.PAA05591@cse.psu.edu>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] C-program error..
Date: Fri, 16 Jun 2000 15:50:42 -0400
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In your example, s in recvit() is expected (by recv()) to point to
storage for the data sent on the channel (all 32 bytes worth),
but you have left it uninitialized.

Also, print() has an internal buffer of 4096 bytes; you need to
increase the stack size or you'll get mysterious errors caused
by stack corruption.

Try this version:

#include <u.h>
#include <libc.h>
#include <thread.h>

#define STACKSIZE (8*1024)

void
recvit(void *arg)
{
	char *s;
	Channel *in = arg;

	recv(in, &s);
	print("%s\n", s);
	free(s);
}

void
threadmain(int argc, char *argv[])
{
	char *m;
	Channel *sch;

	sch = chancreate(sizeof(char*), 0);
	m = strdup("hello world!");
	print("main: %s\n", m);
	proccreate(recvit, (void *)sch, STACKSIZE);

	send(sch, &m);

	print("done\n");
}