Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Read input from another tty
Top Forums Shell Programming and Scripting Read input from another tty Post 302686469 by bakunin on Tuesday 14th of August 2012 03:49:00 PM
Old 08-14-2012
First off, I'd like to warn you: using backticks is a very, very, bad idea: they are outdated, they have a lot of drawbacks, they are only supported for backwards compatibility purposes (with some scripts from the seventies) and you should forget that they exist. Instead of

Code:
`command`

use

Code:
$(command)

which does the same, only much better.

Quote:
Originally Posted by colinireland
reading in output from a terminal to a variable in the bash script.
terminals don't have output - only processes have output. If you start a process you can redirect its output to <stdout> and/or <stderr> (to your terminal, a file or the device another file descriptor points to). There is no way to redirect the output of a process you don't have started.

If you want to start an xterm and display the output of some process there, you have to:

1. create the terminal window
2. find out the device file attached to it
3. start your process and redirect its output to the device file in question.

I hope this helps.

bakunin
 

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

How to input escape sequences in Linux tty?

More details: Unicode, Framebuffer. I tried to press Esc and then what should follow, letters or brackets, but seems not to work. Probably i do something wrong. If somebody is familiar with escape sequences in the console, how do you do that? Thanks in advance. (4 Replies)
Discussion started by: Action
4 Replies

2. UNIX for Dummies Questions & Answers

read from terminal/keyboard > /dev/tty

Hi, I need to provide more than one character to "> /dev/tty" through terminal/keyboard input, I have this: ok=false while do echo " Enter r1 to reformat " > /dev/tty read choice case $choice in ) echo " bla bla bla " ;; done However, in this way,... (3 Replies)
Discussion started by: Gery
3 Replies

3. Shell Programming and Scripting

Read input

I have a script. #! /bin/bash echo "Enter a word: " read word echo $word That outputs like this.. Enter a word: hello hello But how can i read on the same line the question is printed? Like this.. Enter a word: hello hello (2 Replies)
Discussion started by: cbreiny
2 Replies

4. Shell Programming and Scripting

Help with Bash piped while-read and a read user input at the same time

Hi I am new to writing script and want to use a Bash Piped while-read and read from user input. if something happens on server.log then do while loop or if something happend on user input then do while loop. Pseudocode something like: tail -n 3 -f server.log | while read serverline || read... (8 Replies)
Discussion started by: MyMorris
8 Replies

5. Shell Programming and Scripting

Read Input and go BG

My script needs to get some input from the user and go as a background process and run. I have something like read input. do while ... if .. fi done can i use nohup inside the script?? (7 Replies)
Discussion started by: Antergen
7 Replies

6. Ubuntu

Kernel panics : trying to write / read on tiny tty driver

I'm a beginner to the Linux programming and trying my hands on some device driver examples while practising. The below code (a trimmed down version of tiny_tty.c from ldd3 book) loads perfectly using insmod and I'm able to see it in /proc/tty/drivers , /proc/modules and device nodes are getting... (1 Reply)
Discussion started by: diwsdiwa
1 Replies

7. Shell Programming and Scripting

Read input files and merge them in given order and write them to input one param or one file

Dear Friends, I am looking for a shell script to merge input files into one file .. here is my idea: 1st paramter would be outfile file (all input files content) read all input files and merge them to input param 1 ex: if I pass 6 file names to the script then 1st file name as output file... (4 Replies)
Discussion started by: hyd1234
4 Replies

8. Shell Programming and Scripting

Using read for input over ssh

Hi, I'm using read in a script to prompt and receive input. read -r -p "Do you also want to deploy folder? " response This works fine, however, if I remotely execute the same script via ssh, at this point in the code, I don't see the message at all, but it waits for input. I could echo... (1 Reply)
Discussion started by: say170
1 Replies

9. Shell Programming and Scripting

Read input from Keyboard, do not proceed if no input

Hi, I am working on a script, which requests users to enter input. Ex: read -p "Please enter your email id:" email I don't want users skipping this entry, this has to be mandatory.I dont want to proceed without input. I can do a check if variable $email is empty and proceed if not.But, i... (7 Replies)
Discussion started by: aravindadla
7 Replies

10. Shell Programming and Scripting

Python: Redirecting to tty and reading from tty

In bash, you can do something like this: #!/bin/bash echo -n "What is your name? " > /dev/tty read thename < /dev/tty How can I do the same in python? I have a python script that has the following content: #!/usr/bin/python2.7 import getpass import sys import telnetlib import... (2 Replies)
Discussion started by: SkySmart
2 Replies

LEARN ABOUT OPENSOLARIS

tcflow

tcflow(3C)						   Standard C Library Functions 						tcflow(3C)

NAME

       tcflow - suspend or restart the transmission or reception of data

SYNOPSIS

       #include <termios.h>

       int tcflow(int fildes, int action);

DESCRIPTION

       The tcflow() function suspends transmission or reception of data on the object referred to by fildes, depending on the value of action. The
       fildes argument is an open file descriptor associated with a terminal.

	   o	  If action is TCOOFF, output is suspended.

	   o	  If action is TCOON, suspended output is restarted.

	   o	  If action is TCIOFF, the system transmits a STOP character, which is intended to cause the terminal device to stop  transmitting
		  data to the system.

	   o	  If action is TCION, the system transmits a START character, which is intended to cause the terminal device to start transmitting
		  data to the system.

       The default on the opening of a terminal file is that neither its input nor its output are suspended.

       Attempts to use tcflow() from a process which is a member of a background process group on a fildes associated with its controlling  termi-
       nal,  will cause the process group to be sent a SIGTTOU signal. If the calling process is blocking or ignoring SIGTTOU signals, the process
       is allowed to perform the operation, and no signal is sent.

RETURN VALUES

       Upon successful completion, 0 is returned. Otherwise, -1 is returned and errno is set to indicate the error.

ERRORS

       The tcflow() function will fail if:

       EBADF	 The fildes argument is not a valid file descriptor.

       EINVAL	 The action argument is not a supported value.

       ENOTTY	 The file associated with fildes is not a terminal.

       The tcflow() function may fail if:

       EIO    The process group of the writing process is orphaned, and the writing process is not ignoring or blocking SIGTTOU.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-------------------------------+
       |      ATTRIBUTE TYPE	     |	     ATTRIBUTE VALUE	     |
       +-----------------------------+-------------------------------+
       |Interface Stability	     |Standard			     |
       +-----------------------------+-------------------------------+
       |MT-Level		     |MT-Safe, and Async-Signal-Safe |
       +-----------------------------+-------------------------------+

SEE ALSO

       tcsendbreak(3C), attributes(5), standards(5), termio(7I)

SunOS 5.11							    14 Aug 2002 							tcflow(3C)
All times are GMT -4. The time now is 04:55 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy