If you have more than one version of, say, python installed, then you just change the #! line to pickup the right one. This can be used to run bash, ksh, sed, awk, perl, python, ruby, etc, etc. One of the clever features of UNIX is the #! line on scripts. There is no magic here, it is just like associating. But this file extension association is just a set of lookups in the Windows registry (HKEY_CLASSES_ROOT). A Windows graphics program has a "Main Window" associated with it, but it can if it wishes create a console as well! They don't usually, but they can.Ĭmd.exe scripts have. Some people think that is the same as cmd.exe (and even worse call it a "DOS box"), but it is not, it just uses the same console APIs. It means they have a console window, that's the monochrome rectangle you see. For example telnet and python are both console programs. Most UNIX/Linux people would not call a GUI a shell, but that's just semantics.Ĭmd.exe is a console program, and there are lots of those. In other words a shell is just a program that runs other programs. Microsoft consider Windows Explorer to be a shell. It is a shell, depending on your definition of what a shell is. So, cmd.exe is not a terminal emulator because it is a Windows application running on a Windows machine. It will be pretending to be one of those ancient terminals that are nowadays only found in museums. That is what a terminal emulator like putty is. Of course Microsoft's Windows is a totally alien operating system so far as UNIX is concerned, so it has to pretend to be a UNIX terminal. The database has control information for xterm, and the TERM variable is set accordingly. In comes graphics, specifically Xterm, and a terminal window. The database was accessed depending on the setting of the TERM environment variable, which is still used. So a database of terminal instructions was created, first called termcap and then terminfo. The problem is that all these terminals were different, and had to be driven differently. IBM, HP, and others all had their own devices as well. Terminal emulators like putty emulate those. One of the most successful at that time was DEC (since taken-over by HP) who had a series of terminals used on their VAX computers: vt52 was the most basic, vt100, vt220, vt320 gave increasing functionality. There were many manufacturers of terminal devices. Most UNIX access was through character driven terminals (asynchronous at that). Graphics devices were highly specialised (and expensive), and uncommon. Linux is based on UNIX, which goes back to the days of dumb terminals. That's really it - you should not look for similarities when there are none. The architecture of Linux and Windows is different.
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