So, no init system or anything? Your terminal probably hasn't been set up. This is a surprisingly tricky bit of "magic" done with a special syscall which we're for the most part happy to let some linux distribution do for us.
One workaround for it, funny enough, could be ssh-ing into your device. A virtual terminal should be close enough.
I was sure that busybox had a utility for it, and their faq turns out to have that and a better explanation what it does:
Quote:
"Why do I keep getting "sh: can't access tty; job control turned off" errors? Why doesn't Control-C work within my shell?"
Job control will be turned off since your shell can not obtain a controlling terminal. This typically happens when you run your shell on /dev/console. The kernel will not provide a controlling terminal on the /dev/console device. You should run your shell on a normal tty such as tty1 or ttyS0 and everything will work.
Example: you booted into your machine with init=/bin/sh and got "sh: can't access tty" error because sh has its stdio opened to /dev/console. You want to reopen stdio to, say, /dev/tty1 and thus acquire a controlling tty.
These 2 Users Gave Thanks to Corona688 For This Post:
In Darwin, when typing "ifconfig en0 media 10baseT/UTP mediaopt half-duplex" I recieve the error message "ifconfig: SIOCSIFMEDIA: Operation not permitted". The same thing occurs when I sudo the command. Any suggestions?
Thanks... (1 Reply)
Attempting to break from a case/esac paragraph while inside of a function. When executing the code below, entering the letter 'a', will prove that the directory exists, but the break command works for the if/fi, but not for the case/esac. So, in my example below, if an A is entered, the function... (8 Replies)
Hi there everyone,
I'm using redhat 7.3 at the moment and am currently trying to install chkconfig-1.3.5-3.i386.rpm , but when I type this command:
rpm -Uvh chkconfig-1.3.5-3.i386.rpm
I get the following error:
error: failed dependencies:
chkconfig = 1.2.24 is needed by... (3 Replies)
OS: HP-UX
Programs I want to install: expect and tcl
I'm lost.
I bought the book.
I began reading the book.
I want to install expect.
I've been able to download the .z, and extract it successfully.
But, of course, it apparently needs tcl and possibly tk also, and ... I... (0 Replies)
i just installed Debian Lenny on HP DL380. After the server rebooted, it still asks for me to insert a cd rom. where can I exactly check the settings for the boot menu? Should it use the hard disk since I didnt insert any cd? pls advise (1 Reply)
We currently have a setup with SLES11SP1 where we have an AutoYaST ISO set up for automated network installs. I'm attempting to port this to SP2 to make new installs current, but I'm running into a few problems. The process seems the same, and after running mkisofs to build a new SP2 ISO the... (0 Replies)
Hi Team,
Am trying to open alsamixer via command line but am getting the following error.
$ alsamixer
Home directory /home/root not ours.
ALSA lib pulse.c:229:(pulse_connect) PulseAudio: Unable to connect: Connection refused
cannot open mixer: Connection refused
Even am opening as... (2 Replies)
If run the below code today its creating all directory and getting output files,I f run same code tomorrow I am getting error.
can any one give suggestion to sortout this error.
OSError: no such file or directory : '062518'My code looks like this
import paramiko
import sys
import os ... (8 Replies)
Discussion started by: haribabu2229
8 Replies
LEARN ABOUT FREEBSD
smrsh
SMRSH(8) System Manager's Manual SMRSH(8)NAME
smrsh - restricted shell for sendmail
SYNOPSIS
smrsh -c command
DESCRIPTION
The smrsh program is intended as a replacement for sh for use in the ``prog'' mailer in sendmail(8) configuration files. It sharply limits
the commands that can be run using the ``|program'' syntax of sendmail in order to improve the over all security of your system. Briefly,
even if a ``bad guy'' can get sendmail to run a program without going through an alias or forward file, smrsh limits the set of programs
that he or she can execute.
Briefly, smrsh limits programs to be in a single directory, by default /usr/libexec/sm.bin, allowing the system administrator to choose the
set of acceptable commands, and to the shell builtin commands ``exec'', ``exit'', and ``echo''. It also rejects any commands with the
characters ``', `<', `>', `;', `$', `(', `)', `
' (carriage return), or `
' (newline) on the command line to prevent ``end run'' attacks.
It allows ``||'' and ``&&'' to enable commands like: ``"|exec /usr/local/bin/filter || exit 75"''
Initial pathnames on programs are stripped, so forwarding to ``/usr/bin/vacation'', ``/home/server/mydir/bin/vacation'', and ``vacation''
all actually forward to ``/usr/libexec/sm.bin/vacation''.
System administrators should be conservative about populating the sm.bin directory. For example, a reasonable additions is vacation(1),
and the like. No matter how brow-beaten you may be, never include any shell or shell-like program (such as perl(1)) in the sm.bin direc-
tory. Note that this does not restrict the use of shell or perl scripts in the sm.bin directory (using the ``#!'' syntax); it simply dis-
allows execution of arbitrary programs. Also, including mail filtering programs such as procmail(1) is a very bad idea. procmail(1)
allows users to run arbitrary programs in their procmailrc(5).
COMPILATION
Compilation should be trivial on most systems. You may need to use -DSMRSH_PATH="path" to adjust the default search path (defaults to
``/bin:/usr/bin'') and/or -DSMRSH_CMDDIR="dir" to change the default program directory (defaults to ``/usr/libexec/sm.bin'').
FILES
/usr/adm/sm.bin - default directory for restricted programs on most OSs
/var/adm/sm.bin - directory for restricted programs on HP UX and Solaris
/usr/libexec/sm.bin - directory for restricted programs on FreeBSD (>= 3.3) and DragonFly BSD
SEE ALSO sendmail(8)
$Date: 2013-11-22 20:52:00 $ SMRSH(8)