Download Cygwin User's Guide

Chapter 1. Cygwin Overview
1.1. What is it?
The Cygwin tools are ports of the popular GNU development tools and utilities for
Windows NT and 9x. They function through the use of the Cygwin library which
provides the UNIX system calls and environment that these programs require.
With the tools installed, programmers may write Win32 console or GUI applications
that make use of the standard Microsoft Win32 API and/or the Cygwin API. As a
result, it is possible to easily port many significant UNIX programs without the need
for extensive changes to the source code. This includes configuring and building most
of the available GNU software (including the development tools included with the
Cygwin distributions). Even if the compiler tools are of little to no use to you, you may
have interest in the many standard UNIX utilities. They can be used both from the bash
shell (provided) or from the command.com.
1.2. Are the Cygwin tools free software?
Yes. Parts are GNU software (gcc, gas, ld, etc...), parts are covered by the standard X11
license, some of it is public domain, some of it was written by Red Hat and placed
under the GPL. None of it is shareware. You don’t have to pay anyone to use it but you
should be sure to read the copyright section of the FAQ for more information on how
the GNU General Public License may affect your use of these tools. If you intend to
port a proprietary application using the Cygwin library, you may want the Cygwin
proprietary-use license. For more information about the proprietary-use license, please
go to http://www.redhat.com/software/tools/cygwin/. Customers of the native Win32
GNUPro should feel free to submit bug reports and ask questions through the normal
channels. All other questions should be sent to the project mailing list
<[email protected]>.
1.3. A brief history of the Cygwin project
The first thing done was to enhance the development tools (gcc, gdb, gas, et al) so that
they could generate/interpret Win32 native object files.
1