Before starting bash, you may set some environment variables. A .bat file is provided where the most important ones are set before bash in launched. This is the safest way to launch bash initially. The .bat file is installed in the root directory that you specified during setup and pointed to in the Start Menu under the "Cygwin" option. You can edit it this file your liking. The CYGWIN variable is used to configure many global settings for the Cygwin runtime system. Initially you can leave CYGWIN unset or set it to tty (e.g. to support job control with ^Z etc...) using a syntax like this in the DOS shell, before launching bash. C:\> set CYGWIN=tty notitle glob The PATH environment variable is used by Cygwin applications as a list of directories to search for executable files to run. This environment variable is converted from Windows format (e.g. C:\Windows\system32;C:\Windows) to UNIX format (e.g., /cygdrive/c/Windows/system32:/cygdrive/c/Windows) when a Cygwin process first starts. Set it so that it contains at least the x:\cygwin\bin directory where "x:\cygwin is the "root" of your cygwin installation if you wish to use cygwin tools outside of bash. This is usually done by the batch file you're starting your shell with. The HOME environment variable is used by many programs to determine the location of your home directory and we recommend that it be defined. This environment variable is also converted from Windows format when a Cygwin process first starts. It's usually set in the shell profile scripts in the /etc directory. The TERM environment variable specifies your terminal type. It is automatically set to cygwin if you have not set it to something else. The LD_LIBRARY_PATH environment variable is used by the Cygwin function dlopen () as a list of directories to search for .dll files to load. This environment variable is converted from Windows format to UNIX format when a Cygwin process first starts. Most Cygwin applications do not make use of the dlopen () call and do not need this variable. Cygwin's heap is extensible. However, it does start out at a fixed size and attempts to extend it may run into memory which has been previously allocated by Windows. In some cases, this problem can be solved by adding an entry in the either the HKEY_LOCAL_MACHINE (to change the limit for all users) or HKEY_CURRENT_USER (for just the current user) section of the registry. Add the DWORD value heap_chunk_in_mb and set it to the desired memory limit in decimal MB. It is preferred to do this in Cygwin using the regtool program included in the Cygwin package. (For more information about regtool or the other Cygwin utilities, see or use each the --help option of each util.) You should always be careful when using regtool since damaging your system registry can result in an unusable system. This example sets memory limit to 1024 MB: regtool -i set /HKLM/Software/Cygwin/heap_chunk_in_mb 1024 regtool -v list /HKLM/Software/Cygwin Exit all running Cygwin processes and restart them. Memory can be allocated up to the size of the system swap space minus any the size of any running processes. The system swap should be at least as large as the physically installed RAM and can be modified under the System category of the Control Panel. Here is a small program written by DJ Delorie that tests the memory allocation limit on your system: main() { unsigned int bit=0x40000000, sum=0; char *x; while (bit > 4096) { x = malloc(bit); if (x) sum += bit; bit >>= 1; } printf("%08x bytes (%.1fMb)\n", sum, sum/1024.0/1024.0); return 0; } You can compile this program using: gcc max_memory.c -o max_memory.exe Run the program and it will output the maximum amount of allocatable memory. To set bash up so that cut and paste work properly, click on the "Properties" button of the window, then on the "Misc" tab. Make sure that "QuickEdit mode" and "Insert mode" are checked. These settings will be remembered next time you run bash from that shortcut. Similarly you can set the working directory inside the "Program" tab. The entry "%HOME%" is valid, but requires that you set HOME in the Windows environment. Your home directory should contain three initialization files that control the behavior of bash. They are .profile, .bashrc and .inputrc. The Cygwin base installation creates stub files when you start bash for the first time. .profile (other names are also valid, see the bash man page) contains bash commands. It is executed when bash is started as login shell, e.g. from the command bash --login. This is a useful place to define and export environment variables and bash functions that will be used by bash and the programs invoked by bash. It is a good place to redefine PATH if needed. We recommend adding a ":." to the end of PATH to also search the current working directory (contrary to DOS, the local directory is not searched by default). Also to avoid delays you should either unset MAILCHECK or define MAILPATH to point to your existing mail inbox. .bashrc is similar to .profile but is executed each time an interactive bash shell is launched. It serves to define elements that are not inherited through the environment, such as aliases. If you do not use login shells, you may want to put the contents of .profile as discussed above in this file instead. shopt -s nocaseglob will allow bash to glob filenames in a case-insensitive manner. Note that .bashrc is not called automatically for login shells. You can source it from .profile. .inputrc controls how programs using the readline library (including bash) behave. It is loaded automatically. For full details see the Function and Variable Index section of the GNU readline manual. Consider the following settings: # Ignore case while completing set completion-ignore-case on # Make Bash 8bit clean set meta-flag on set convert-meta off set output-meta on The first command makes filename completion case insensitive, which can be convenient in a Windows environment. The next three commands allow bash to display 8-bit characters, useful for languages with accented characters. Note that tools that do not use readline for display, such as less and ls, require additional settings, which could be put in your .bashrc: alias less='/bin/less -r' alias ls='/bin/ls -F --color=tty --show-control-chars'