Python Pty Shells

The pty module defines operations for handling the pseudo-terminal concept: starting another process and being able to write to and read from its controlling terminal programmatically. spawn("/bin/sh")' (pty = psuedo tty) As an added bonus, type this as well:. With over 100 different Python assignments to complete this course will ensure you'll be able to write python code with ease. Discover how to prepare data with pandas, fit and evaluate models with scikit-learn, and more in my new book, with 16 step-by-step tutorials, 3 projects, and full python code. Python TTY Reverse Shell Over IPv6 One-Liner Most newer systems come with IPv6 enabled by default, yet many folks continue to forget or are unsure of how to secure IPv6. Disclaimer, if you use ZSH, sh, or Fish, this might actually break your shell. Instructions for running directly in the shell, or on clusters using the TORQUE and Cobalt job schedulers are described in the following sections. Spawning a TTY shell after gaining access to a system So, beforehand, I hope this isn't considered a "Howtohack" question because I already got root access to my vulnerable VM (Kioptrix Level 1). python -c 'import pty; pty. The builder contains a dropdown with the various categories of Python modules such as CGI, File, etc. 堡垒机执行流程: 管理员为用户在服务器上创建账号(将公钥放置服务器,或者使用用户名密码) 用户登陆堡垒机,输入堡垒机用户名密码,现实当前用户管理的服务器列表. Process - Sort through data, analyse and prioritisation. They are extracted from open source Python projects. Problem was, that it would run under the www-data user and trying to su to root gave me the following message. Automatic conversion of text output from remote system's charset to Unicode-based strings. class collections. - Implemented solutions within Python, Selenium, Webservices(flask), Acurity Architect - Designed and implemented multi-threaded frameworks. Searching vulnerabilities for SimpleHTTP v0. Pepkor IT is a dynamic IT company that delivers value-driven IT solutions to the Pepkor group. Pygame extends Python, adopts Python’s philosophy, and aims to be easy to use. Set TTY mode. Ptysh is not the only route shell, the shell is customizable, so you can normally use. call(cmd), or p=subprocess. Problem was, that it would run under the www-data user and trying to su to root gave me the following message. Welcome to pySerial’s documentation¶. Try using the chsh command instead: chsh -s /bin/bash The -s flag will make the new shell (Bash in this case) your login shell, going forward. When the shell exits, the channel will be closed and can't be reused. Python Library Reference. The SSHClient exec_command¶ Now that I've managed to get a connection going it's time to turn my attenttion to actually doing things on the machine. How to pass the OSCP. Provided to YouTube by Valleyarm Digital Distribution Pearly Shells · Pacific Island Singers South Pacific ℗ Glory Days Music under license from V&H Holdings Pty Ltd Released on: 2014-01-20. See the complete profile on LinkedIn and discover Tsholo’s connections and jobs at similar companies. Because pseudo-terminal handling is highly platform dependent, there is code to do it only for Linux. Most shells also manage foreground and background processes, command history and command line editing. View Craig Steven Wright’s professional profile on LinkedIn. Post exploitation; Escaping limited interpreters; Linux elevation of privileges, manual testing; Scripts to run; Exploits worth running. First things first -- once you get your shell, hit the enter key a few times. Welcome to garage. By joining you are opting in to receive e-mail. Jack Wallen shows some of the strategies you can take when your Linux workstation fails to start. Upgrading a netcat shell to a fully functioning TTY is pretty straight forward. Adeliia má na svém profilu 6 pracovních příležitostí. This time around we will be discussing about Hack The Box which has become very famous for various machines and the levels within it. The command works like this: python watermark. Python Classes/Objects. Think all the goodness SSH is doing for you, could we attempt. 10 reasons to turn your Access applications into Web-based applications. Anaconda Group Pty Ltd Austin, TX, US 4 weeks ago Be among the first 25 applicants. - Experienced in writing build and installer scripts in Python / PowerShell for continuous integration tools like Jenkins, Bamboo. This is needed on the Ansible control machine to be reasonably efficient with connections. please if you could guide me the way to read pdf file in python. 1 year, 10 months ago. The Python source code builder can be launched using the Code - Bulders - Python menu item, or by selecting the Python code builder option of the Python sidekick. python-pty-shells. Reverting to the current behaviour if folks actually want that would just be a matter of passing the file in directly, rather than piping it via stdin: "python script. While this example is quite superfluous in that you could just use the shell >> redirection to append to the file, you could also include a network link into the mix with minimal effort using socat as shown below. Any POSIX system (UNIX) with a working pty module should be able to. This module encapsulates the access for the serial port. If you are a C++ or Python developer and have some time to spare you may join the ClamWin Free Antivirus Project and help to improve it; Or please click here to make a donation and support further development of ClamWin Free Antivirus. If your system is reporting errors that the file descriptor is bad, one of possible causes is that file system is corrupt and thus, you require restoring from backup. 5 - Object Injection 'x-forwarded-for' Header Remote Code Execution. Write your code in this editor and press "Run" button to execute it. 7 are: PEP 539, new C API for thread-local storage. Python when combined with Tkinter provides a fast and easy way to create GUI applications. Supports custom channels. To verify that Python installed correctly, open a terminal or shell and run the following command. ACM/ICPC ActionScript Android Ant API ASP C# C++ CentOS Docker DotNet Flash Google HTML iOS Java JavaScript Jquery Linux MacOS nginx Objective-C OpenSSL PHP PostgreSQL Python RQAlpha SEO Shell SQL SSL Ubuntu VB VBscript Web2. If you have a non-tty-shell there are certain commands and stuff you can't do. The script indicates that it must be executed by a shell located at /bin/bash^M. Let’s get started. local exploit for Linux platform. The subprocess module provides the following enhancements over previous functions:. Octopus Deploy is an automated deployment and release management tool used by leading continuous delivery teams worldwide. The return value is an open file object connected to the pipe, which can be read or written depending on whether mode is 'r' (default) or 'w'. Store We should have lots of new posts soon about the products we carry! Our store is all about the customer and getting them quality and a great experience at the right price point. In part 2 we have configured master server and child servers for Secure Shell protocol to execute programs remotely over the network. conch A flexible library for shelling out in Clojure porcelain Work with external processes like a boss dumb-init A minimal init system for Linux containers go-shell. Makati City, PH 4 weeks ago. The coding assessments are created by industry experts. Please make sure to split out the GUI framework portion for your question. invoke_shell ssh example python exec_command send get_pty execute stdout sftp Long-running ssh commands in python paramiko module(and how to end them) I want to run a tail-f logfile command on a remote machine using python's paramiko module. Screenshot: For the discerning hacker, who wants SSL/TLS encryption on their shells, you can use ncat (from nmap) with the --ssl argument on both ends instead of netcat, however ncat being installed is less likely. Created in the early 1990s by Guido van Rossum, Python has grown in popularity over the years. This makes it hard for developers to choose. These users are not meant to have shells as they don't interact with the system has humans do. 0 (fixed link script) 858941 486 7180 866607 d392f busybox-1. It provides backends for Python running on Windows, OSX, Linux, BSD (possibly any POSIX compliant system) and IronPython. To use a pty instead of the default behavior, specify pty=True. cwd - Working directory. I've spent hours upon hours of trying to troubleshoot this, but this is beyond me: Here is the code. He has over a decade of programming and instructional experience, and currently is a coordinator for the Silicon Valley-San Francisco Bay Area Python users group (BayPIGgies), a volunteer moderator for the Python Tutor mailing list, and the author of Core Python Programming, the Python book in Prentice Hall's Core series. The Python source code builder can be launched using the Code - Bulders - Python menu item, or by selecting the Python code builder option of the Python sidekick. I build the command line string, but when I try to run subprocess. This page is simply for reference only, as such, content may change frequently. Mateng is close in that I think you're probably running Bourne Shell. system(cmd), I get prompted for my login password. Python PTY backdoors - full PTY or nothing! Insecurety Research (2013) The following is a collection of bind and reverse shells which give you a fully working PTY. This program executes any shellcode that you give it. For new articles and tutorials please refer to Nirpy Research from now on. It also provides SSH tunneling capabilities. Because pseudo-terminal handling is highly platform dependent, there is code to do it only for Linux. Tty (terminal equipment referred to): tty word from Teletypes, or teletypewriters, originally referring to the teletype, a printer via a serial line using the keyboard to read and send messages through things, then this thing is to replace the keyboard and monitor, so now more appropriate to call the terminal. OK, I Understand. pty_process. Currently the code is not interactive because I have to pre-code all my commands. After we had the proper shell, we ran the lsb_release command to get the information about the Linux version on the target machine. The pty module defines operations for handling the pseudo-terminal concept: starting another process and being able to write to and read from its controlling terminal programmatically. Integrated Terminal. Go ahead and download hg38. ACM/ICPC ActionScript Android Ant API ASP C# C++ CentOS Docker DotNet Flash Google HTML iOS Java JavaScript Jquery Linux MacOS nginx Objective-C OpenSSL PHP PostgreSQL Python RQAlpha SEO Shell SQL SSL Ubuntu VB VBscript Web2. py is just a tiny, portable python file which did not see many changes) Bug Report Steps to Reproduce: I wrote a very simple python remote shell: #!/usr/bin/env python3 import pty pty. Lets recap what we have done so far. The most recent version of the Cygwin DLL is 3. A new Channel is opened and the requested command is executed. Most shells also manage foreground and background processes, command history and command line editing. ly/2EzoUDo bit. 1106 by executing the ifconfig command in his TTY shell. Shell Spawning. Let’s check out the /bin/ directory to see if we can view any contents. Fatma indique 3 postes sur son profil. This is all using python 2. I’m going to reference the Reverse Shell Cheat Sheet by Pentestmonkey. a Medically trained Computer Scientist Python Perl Shell Java Go Bootstrap HTML5/SCSS Web Dev. I sometimes even manually test it with Python 1. In part 1 we had developed a python program that takes input from shell and returns the log analysis output. matplotlib dapat digunakan di dalam script Python, shell Python dan ipython (ala MATLAB ®* or Mathematica ®), server aplikasi web, dan enam GUI toolkit. Note the rows and columns (say they are 40 and 160 respectively). Bir sızma testinde hedef üzerinde RCE yada File Upload zafiyetleri tespit etmiş ve bu zafiyet üzerinden kendinize reverse/bind shell almış olabilirsiniz ancak her zaman bu yeterli olmayacak, aldığınız shell non-interactive bir shell olacaktır. spawn("/bin/sh")' Tab auto completion on a reverse shell Ctrl+z to background the netcat session then stty raw -echo fg then enter to return the session to. htaccess" who disalow that type of extension as well, by the way if you try to bypass, by modify any image extension, it won't work,. Bind shell. This version of Pexpect requires Python 3. path是python的搜索模块的路径集,是一个list 可以在python 环境下使用sys. even fabfile implementation is up to python 2. The main features of Pexpect require the pty module in the Python standard library, which is only available on Unix-like systems. Spawning a pty from a php shell Earlier today, I was performing a test, had dropped a php shell on the web server and gotten a reverse shell. It also describes some of the optional components that are commonly included in Python distributions. The downside is that you most probably will have to build/install this tool on the target server as it is not a default utility in most unix-like distributions. This program executes any shellcode that you give it. pty PTY interface for Go halfempty A fast, parallel testcase minimization tool. It was made with reference to the 'zebra vtysh'. With over 100 different Python assignments to complete this course will ensure you'll be able to write python code with ease. NET initiative. (8 replies) Hi I want to write a python script that runs rsync on a given directory and host. - Experienced in writing build and installer scripts in Python / PowerShell for continuous integration tools like Jenkins, Bamboo. 6 (jessie) Python 3. Today we’ll describe another visualisation that is available with Plotly for Python. Offensive Security did a fantastic job in explaining Buffer Overflows, It is hard at first but the more you do it the better you understand. Unlike other Expect-like modules for Python, Pexpect does not require TCL or Expect nor does it require C extensions to be compiled. It's a fork and rebuilt version of " Term " package. When you run a Python script, the interpreter converts a Python program into something that that the computer can understand. When the shell exits, the channel will be closed and can't be reused. https://highon. Paramiko has two ways to work with the shell - interactively using invoke_shell and non-interactively using exec_command. Adapt - Customize the exploit, so it fits. It should work on any platform that supports the standard Python pty module. py from Python-3. To get an interactive job on a session, provide the --pty /bin/bash flag to srun, srun --pty /bin/bash. The problem Suppose you want to spawn a system process in python and you want to intercept the stdout of the process and redirecting it on a gtk. Think all the goodness SSH is doing for you, could we attempt. I realized it must be written in C and ported for as many operating systems as possible. Basically, you are asking about writing a terminal emulator, where you'll need to convert the keypress events of your widget to the stdin stream you send to the pty, and handle the display and output of the stream coming out of the stdout of the pty. It can be used for automated software testing. This list represent an comprehensive cheat sheet of shells and other related stuff. Vtysh is an integrated shell for Quagga routing software. Hacker Fest:2019 VM is made by Martin Haller. Makati City, PH 4 weeks ago. 2) hangs if TERM is not set. pty — Pseudo-terminal utilities¶ The pty module defines operations for handling the pseudo-terminal concept: starting another process and being able to write to and read from its controlling terminal programmatically. TTY Shell Spawning. Cancel Anytime. A terminal refers to a wrapper program which runs a shell. system() when dealing with system administration tasks in Python. They are extracted from open source Python projects. In addition to my own contributions, this compilation is possible by other compiled cheatsheets by g0tmilk, highon. My OS: Debian GNU/Linux 8. I'm rewriting a Bash script I wrote into Python. The ndk-build script builds projects that use the NDK's Make-based build system. PuTTY: a free SSH and Telnet client. Subprocess Overview For a long time I have been using os. This should work on most Borne/Bash or Csh style shells. Pexpect allows your script to spawn a child application and control it as if a human were typing commands. These are not full instructions on how to setup the full environment, please let me know if you are interested in such a thing. As you can observe the result from given below image where the attacker has successfully accomplish targets system TTY shell. The crux of that script was. This gives me a weird string format errors. Octopus Deploy is an automated deployment and release management tool used by leading continuous delivery teams worldwide. The main reason for that, was that I thought that was the simplest way of running Linux commands. an interpreted, interactive, object-oriented programming language-c command Specify the command to execute (see next section). I do these keywords - java OAuth/OAuth 2. Supposedly, the attacker was able to execute a python script through an RCE (Remote Code Execution) vulnerability on a web server. profile file, which is read by login shells only: if test -t 0 ; then script exit fi You should also avoid use of script in command pipes, as script can read more input than you would expect. Several versions of Python are available on the cluster. 3 - 'overlayfs' Local Privilege Escalation ; Make sure you use the proper one according to the kernel version! Lab 2: Mr. If you do not see something like the output above, make sure python is working (try python -V) to check the version and you are in the right location. I don't know why but it seems like the first carriage return has garbage sitting behind it and hitting the enter key flushes that out. i thought about a long crank, but i. But you shouldn't be editing your /etc/passwd file directly. Search the world's information, including webpages, images, videos and more. com "ssh second. Several Shell programs exist, Bash being arguably the most commonly used shell today. What I can't figure out is how to have the full login shell open and then have the command run inside that shell. Using Python to get a TTY I grabbed this snippet from a slide posted at a CTF I attended earlier this year. The ndk-build script builds projects that use the NDK's Make-based build system. In order to compromise a python shell, you can use reverse_Python payload along msfvenom as given in below. Today's top 13 Shell Project Engineer jobs in Singapore. spawn("/bin/sh")' Tab auto completion on a reverse shell Ctrl+z to background the netcat session then stty raw -echo fg then enter to return the session to. 3 authenticated remote reverse shell code execution exploit. Python shell. py from Python-3. It offers a higher-level interface than some of the other available modules, and is intended to replace functions such as os. Send signals to remote shell or command. Go ahead and download hg38. Hour of Code: Frozen Fractals Lesson Plan. (Linux) privilege escalation is all about: Collect - Enumeration, more enumeration and some more enumeration. pty_process. It can be used to break out from restricted environments by spawning an interactive system shell. These are not full instructions on how to setup the full environment, please let me know if you are interested in such a thing. pty is a Python module which defines operations related to the pseudo-terminal concept, it can create another process, and from the controlling terminal, it can read/write to the new process. Python OS File/Directory Methods - The os Python module provides a big range of useful methods to manipulate files and directories. recv(1024), shell=True, stdout. produce coloured output), how can that output be redirected in a pipeline while preserving the changed behavi. The crux of that script was. Many systems and network administrators also find it useful for tasks such as network inventory, managing service upgrade schedules, and monitoring host or service uptime. All elements on this template are editable from a Google SLides shape, no need another software, editing just on Google SLides, input your content, replace your image into placeholder, change the color, and , all. This page is simply for reference only, as such, content may change frequently. let me tell you all my experience, I try to connect from linux to windows via ssh, had servers with openssh and others with freessh. BeOpen PythonLabs Correo electrónico: [email protected] matplotlib dapat digunakan di dalam script Python, shell Python dan ipython (ala MATLAB ®* or Mathematica ®), server aplikasi web, dan enam GUI toolkit. Pty (class in deployer. The Python source code builder can be launched using the Code - Bulders - Python menu item, or by selecting the Python code builder option of the Python sidekick. You can work interactively on a node from the Linux shell command line by starting a job in the interactive queue. Store We should have lots of new posts soon about the products we carry! Our store is all about the customer and getting them quality and a great experience at the right price point. The downside is that you most probably will have to build/install this tool on the target server as it is not a default utility in most unix-like distributions. 99% of the time, adding pty=True to your run call will make things work as you were expecting. See the complete profile on LinkedIn and discover Ren’s connections and jobs at similar companies. PHP & Python Projects for ₹600 - ₹1500. They are extracted from open source Python projects. job) wall_time_limit (in module saga. It makes Python an even better replacement language for over-complicated shell scripts. Problem was, that it would run under the www-data user and trying to su to root gave me the following message. js and Electron Latest release 0. Popen(cmd, shell=True),or os. However I can't undestand how to make this shell interactive so that it reads whats in the terminal, and if I put a command in the terminal & hit carridge return, it executes that and reads back the output. Use -l or -L to list available signals. PTYProcess method) WALL_TIME_LIMIT (in module saga. *() and commands. Friends its very simple. Note the rows and columns (say they are 40 and 160 respectively). Set environment variables. The default signal for skill is TERM. There is more specific documentation for the Android. It can be used for automated software testing. This is often used to baffle programs which insist on reading from the controlling terminal. Pexpect is in the spirit of Don Libes’ Expect, but Pexpect is pure Python. The command’s input and output streams are returned as Python file-like objects representing stdin, stdout, and stderr. See the complete profile on LinkedIn and discover Liz’s connections and jobs at similar companies. Process - Sort through data, analyse and prioritisation. After looking at paramikos' exec_command() function, I realized it's not suitable f. From Java to Python, SQL to C#, web development to shell scripting: we can help you become a better programmer. Vtysh is an integrated shell for Quagga routing software. View mapurunyane samuel TOLAMO’S profile on LinkedIn, the world's largest professional community. 2 869074 516 7364 876954 d619a busybox-1. ly/2s4qWl4 bit. I don't know why but it seems like the first carriage return has garbage sitting behind it and hitting the enter key flushes that out. SANS Penetration Testing blog pertaining to Pen Test Poster: "White Board"- Python - Raw Shell Terminal provided are now performed by the "TTY" and "PTY" on your. Python PTY backdoors - full PTY or nothing! Insecurety Research (2013) The following is a collection of bind and reverse shells which give you a fully working PTY. Ren has 2 jobs listed on their profile. Today we’ll describe another visualisation that is available with Plotly for Python. The shell is the program which actually processes commands and returns output. Tiny python bind shell. The modules described in this chapter provide interfaces to features that are unique to the Unix operating system, or in some cases to some or many variants of it. Anything afterward is passed as options to python script or command, not interpreted as an option to interpreter itself. python ssh paramiko Using paramiko to send SSH commands was published on October 11, 2012 Sebastian. One of my go-to commands for a long time after catching a dumb shell was to use Python to spawn a pty. Set an environment variable and it "stays" because the shell process is the same through the whole session. Help :/ I can't do cd with this. local is simply a convenience wrapper around the use of the builtin Python subprocess module with shell=True activated. You can write your own Expect scripts to perform batch jobs with the CLI. an interpreted, interactive, object-oriented programming language-c command Specify the command to execute (see next section). Obviously some of this will depend on the system environment and installed packages. Currently, Python has a large number of different functions for process creation. 果然登陆成功了,而且得到了一个python命令提示符界面。这好办,我们import pty这个模块,然后使用spawn ‘/bin/bash’命令来进入系统的bash shell。我们来看下mamadou用户的家目录,发现flag1. Python is a general purpose. py from Python-3. Since we have a literal BASH session, let’s just use one of the many different methods to pop a reverse shell. Python TTY Shell python -c 'import pty; pty. PuTTY: a free SSH and Telnet client. The subprocess module provides a consistent interface to creating and working with additional processes. It also has some other challenges as well. To verify that Python installed correctly, open a terminal or shell and run the following command. Currently the code is not interactive because I have to pre-code all my commands. ly/2tnoZ6P bit. How do I log all input and output in a terminal session? Ask Question But will this work if I login to the mysql database from the shell using the following. So I popped the python command in a text file, and did. sftp Terminal emulation type to request when allocating a pty : term_width: Width of terminal requested when allocating a pty :. This version of Pexpect requires Python 3. 3 and subprocess. py" 7) Ahora les reto a que uds me indiquen que paso :D. This is just like the Netcat but with security in mind. Hi Frank, i have found your website very useful as i am python learner. A pty is a kernel-level object which processes can write data to and read data from, a bit like a pipe. You must open a new channel if you wish to open another shell. This can happen if you upload reverse shells on a webserver, so that the shell you get is by the user www-data, or similar. Reverse Shell: We’ve got some basic information on the box but, let’s get a shell to do more in-depth digging. Pexpect is in the spirit of Don Libes' Expect, but Pexpect is pure Python. system(), os. Upgrading a netcat shell to a fully functioning TTY is pretty straight forward. You can vote up the examples you like or vote down the ones you don't like. PuTTY: a free SSH and Telnet client. 0 is the newest major release of the Python language, and it contains many new features and optimizations. Because pseudo-terminal handling is highly platform dependent, there is code to do it only for Linux. General information and availability ===== 1. profile file, which is read by login shells only: if test -t 0 ; then script exit fi You should also avoid use of script in command pipes, as script can read more input than you would expect. Currently, Python has a large number of different functions for process creation. It contains the Python interpreter, editor, QPYPI, QRCode reader and some amazing features for Android. matplotlib dapat digunakan di dalam script Python, shell Python dan ipython (ala MATLAB ®* or Mathematica ®), server aplikasi web, dan enam GUI toolkit. Hi I am trying to execute a sed command inside paramiko which finds and deletes the particular string from a file But sed command doesnt work inside paramiko python pre { overflow:scroll; margin:2px; | The UNIX and Linux Forums. It can be used to break out from restricted environments by spawning an interactive system shell. Currently the code is not interactive because I have to pre-code all my commands. Seguesoft NETCONFc™ is an easy-to-use NETCONF / RESTCONF client and Python scripting tool for NETCONF/YANG developers and test engineers. I do these keywords - java OAuth/OAuth 2. 溢出提权获得更多知识可以+875259688# python –c‘impotr pty;pty. Set an environment variable and it "stays" because the shell process is the same through the whole session. The pty module defines operations for handling the pseudo-terminal concept: starting another process and being able to write to and read from its controlling terminal programmatically. This version of Pexpect requires Python 3. Solid understanding of data structures & common algorithms Understanding of time-complexity of algorithms. The SSH protocol (also referred to as Secure Shell) is a method for secure remote login from one computer to another. getpid()): # apparently python GC's modules before class instances so, here # we have some hax to ensure we can restore the terminal state. py | python". This version of Pexpect requires Python 3. Buffer Overflow. It can send back a reverse shell to a listening attacker to open a remote network access. please bid for minimum and so that i can consider u and send you the task thanks. General colouring is a pale brown to honey, with chocolate markings that are usually in larger blotches. Delete a remote folders and files in Ansible [crayon-5db4627a6d6b0728573133/] Sync files from a directory inside of another directory in Ansible [crayon-5db4627a6d6b7273430907/]. Females usually lay 6 - 15 large, hard-shelled eggs. pty — Pseudo-terminal utilities¶ The pty module defines operations for handling the pseudo-terminal concept: starting another process and being able to write to and read from its controlling terminal programmatically. The downside is that you most probably will have to build/install this tool on the target server as it is not a default utility in most unix-like distributions. I'm rewriting a Bash script I wrote into Python. If the program’s available globally but you’d prefer to avoid running an extra Python program at shell startup, you can cache the output of the command in its own file; where this file lives is entirely up to you and how your shell is configured. This can be useful if you are using Python primarily for the enhanced control flow it offers over most system shells and still want convenient access to other shell features such as shell pipes, filename wildcards, environment variable expansion, and expansion of ~ to a user's home directory.