cygnus(3)

NAME

cygnus - Open a Cygwin BASH window
%cygnus-bin-path - Cygwin BASH directory
%cygnus-hilight - Cygwin shell hilight enable flag
%cygnus-prompt - Cygwin shell prompt

PLATFORM

Windows '95/'98/NT - win32 ONLY

SYNOPSIS

cygnus

%cygnus-bin-path "path"
%cygnus-hilight [0|1]
%cygnus-prompt "hilightString"

DESCRIPTION

cygnus creates an interactive BASH shell window within a MicroEmacs buffer window, providing a UNIX command line facility within the Microsoft Windows environment. This is a preferable environment to the MS-DOS shell and is certainly far more comfortable for those people familiar with UNIX.

Within the window BASH commands may be entered and executed, the results are shown in the window. Within the context of the BASH shell window then directory naming conforms to the cygwin standard conventions (as opposed to the Microsoft directory naming).

On running cygnus a new buffer is created called *cygnus* which contains the shell. Executing the command again creates a new shell window called *cygnus1*, and so on. If a cygwin window is killed off then the available window is used next time the command is run.

Additional controls are available within the shell window to control the editors interaction with the window. The operating mode is shown as a digit on the buffer mode line, this should typically show "3", which corresponds to F3. The operating modes are mapped to keys as follows:-

F2


Locks the window and allows local editing to be performed. All commands entered into the window are interpreted by the editors. F2 mode is typically entered to cut and paste from the window, search for text strings etc. In mode 2, a 2 is shown on the mode line.

F3


The normal operating mode, text typed into the window is presented to the shell window. Translation of MicroEmacs commands (i.e. beginning-of-word) are translated and passed to the shell. For interactive use this is the default mode. In mode 3, a 3 is shown on the mode line.

F4


All input is passed to the shell, no MicroEmacs commands are interpreted and keys are passed straight to the shell window. This mode is used where none of the keys to be entered are to be interpreted by MicroEmacs. Note that you have to un-toggle the F4 mode before you can swap buffers as this effectively locks the editor into the window.

F5


Clears the buffer contents. This simply erases all of the historical information in the buffer. The operation of the shell is unaffected.

To exit the shell then end the shell session using "exit" or "C-d" as normal and then close the buffer. A short cut "C-c C-k" is available to kill off the pipe. However, it is not recommended that this method is used as it effectively performs a hard kill of the buffer and attached process

%cygnus-bin-path is a user defined variable that defines the file system location of the cygwin directory. This variable MUST be defined within the user start up script in order for the cygnus command to start the shell. With a default installation of cygwin then the settings are typically defined as:-

Release B19

set-variable %cygnus-bin-path "C:/Cygnus/B19/h-i386~1/bin" 

Release B20

set-variable %cygnus-bin-path "c:/cygnus/cygwin-b20/H-i586-cygwin32/bin" 

%cygnus-hilight is a boolean flag which controls how the cygnus command shell window is hilighted. This value MUST be defined within the user start up script prior to executing cygnus if hilighting is to be enabled; by default hilighting is disabled. A value of 1 enables shell hilighting i.e.

set-variable %cygnus-hilight 1 

%cygnus-prompt is an optional variable that is used in conjunction with %cygnus-hilight, it defines the hilighting string identifying the prompt. This allows the prompt to be rendered with a different color. The default prompt is bash-2.01$ and may be hilighted using a definition:-

set-variable %cygnus-prompt "bash-2.01$" 

The user typically overrides the prompt definition within the BASH startup file, a more appropriate definition of the prompt may be:-

set-variable %cygnus-prompt "^[a-z]*@[^>]*>" 

NOTES

The cygnus command uses the ipipe-shell-command(2) to manage the pipe between the editor and the bash shell. The window is controlled by the macro file hkcygnus.emf which controls the interaction with the shell.

The macro cygnus in hkcygnus.emf defines the parameter setup to connect to the cygwin bash shell (Version 19), installed in the default location c:/cygnus. If your installation of cygnus is in a different location then correct the macro to match your install location, preferably correct by creating a mycygnus.emf file in your user directory simply containing a re-defined cygnus macro.

If you have exported some of the cygwin environment variables in your autoexec.bat then you will have to figure out for yourself what variables macro cygnus needs to export - the current configuration is for a vanilla install.

The bash shell is executed with options i, for interactive shell and m to enable job control.

TESTED CONFIGURATIONS

This configuration has only been tested on a Windows '98 installation, whether this works on NT and Windows '95 (OEM SR2) is unknown.

We have only been running "make" operations in the shell and do not know how the likes of "more", "man" or anything other terminal interaction works.

Tested Configurations


Windows '98 (Pentium 120MHz/Pentium Pro 200MHz/Cyrix 300MHz/Pentium II 450MHz)

cygwin version B19.3 - this is the original "cygwin" distribution + the latest "coolview.tar.gz" patch.
cygwin version B20 - the latest cygwin distribution.

BUGS

Break Key


A break in a bash shell is C-c, the macros define the key C-c C-c to perform the break. This sequence is sent to the process but is not enacted by the shell. This is a property of the Bash shell rather than MicroEmacs.

Slow Response


If you are getting a very slow response from the bash shell then check the directory where bash was started. Sometimes there are problems if the shell is started in "c:/" (which is typically "/") then the bash shell is very unresponsive and tends to 'ignore me' for periods of time. If it is started in another location, i.e. "c:/temp" directory, then this problem does not occur.

You can see the start-up location in the top of the buffer when the shell is started.

Prompt at top of buffer


Very, very occasionally the ishell sticks at the top of the buffer with only a couple of lines showing. A swap of the buffers or a quick window resize sorts out the problem. A fix for this problem has been applied but still may occasionally occur.

WinOldAp


Winoldap is created by the Microsoft environment whenever a BASH shell is created. On occasions where processes have terminated badly the user may be prompted to kill these off; this is the normal behaviour of windows. It is strongly advised that all of the BASH processes are killed from within the Bash shell itself and the shell is always exited correctly (i.e. exit) before leaving the editor. The Windows operating system for '95/'98 is not particularly resilient to erroneous processes (for those of us familiar with UNIX) and can bring the whole system down. I believe that NT does not suffer from these problems (much).

Locked Input


There are occasions after killing a process the editor appears to lock up. This is typically a case that the old application has not shut down correctly. Kill off the erroneous task (Alt-Ctrl-Del - End Task) then bring the editor under control using a few C-g abort-command(2) sequences.

SEE ALSO

ipipe-shell-command(2), ishell(3).
Cygnus Win32 home sites www.cygnus.com and www.cygnus.co.uk

(c) Copyright JASSPA 1999
Last Modified: 1999/05/27
Generated On: 1999/12/01