doc/Host-tools-overview: tiffs-mkfs description updated The first version of tiffs-mkfs did not include a journal file in the created FFS, expecting the firmware to create it on first boot. All historical firmwares prior to a recent FC fix (2020-05) contain a bug in that code path, thus images made with the first version of tiffs-mkfs were only acceptable to very recent FC firmwares. tiffs-mkfs has now been extended to include an empty journal in the created FFS, thus the restriction of working with recent fw only has been lifted.

#include <sys/types.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

extern char bootctrl_pwon_cmd[];

static char shell_pathname[] = "/bin/sh";

void
fork_exec_pwon_cmd()
{
	int i;

	i = vfork();
	if (i < 0) {
		perror("vfork");
		exit(1);
	}
	if (i)
		return;
	execl(shell_pathname, "sh", "-c", bootctrl_pwon_cmd, (char *) 0);
	perror(shell_pathname);
	_exit(1);
}

pwon_if_needed()
{
	if (!bootctrl_pwon_cmd[0])
		return(0);
	signal(SIGCHLD, SIG_IGN);
	fork_exec_pwon_cmd();
	return(1);
}