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docs/using_a_linux_chroot.md

+# Using a chroot
+
+If you want to run layout tests and you're not running Lucid, you'll get errors due to version differences in libfreetype. To work around this, you can use a chroot.
+
+# Basic Instructions
+
+  * Run `build/install-chroot.sh`.  On the prompts, choose to install a 64-bit Lucid chroot and activate all your secondary mount points.
+  * sudo edit `/etc/schroot/mount-lucid64bit` and uncomment `/run` and `/run/shm`.  Verify that your mount points are correct and uncommented: for example, if you have a second hard drive at `/src`, you should have an entry like `/src /src none rw,bind 0 0`.
+  * Enter your chroot as root with `sudo schroot -c lucid64`.  Run `build/install-build-deps.sh`, then exit the rooted chroot.
+  * Delete your out/ directory if you had a previous non-chrooted build.
+  * To enter your chroot as normal user, run `schroot -c lucid64`.
+  * Now run `build/gyp_chromium`, compile and run DumpRenderTree within chroot.
+
+
+# Tips and Tricks
+
+## NFS home directories
+The chroot install will be installed by default in /home/$USER/chroot.  If your home directory is inaccessible by root (typically because it is mounted on NFS), then move this directory onto your local disk and change the corresponding entry in `/etc/schroot/mount-lucid64bit`.
+
+## Goma builds
+If you get mysterious compile errors (glibconfig.h or dbus header error), make sure that goma is running in the chroot, or don't use goma for builds inside the chroot.
+
+## Different color prompt
+
+I use the following code in my .zshrc file to change the color of my prompt in the chroot.
+```
+# load colors
+autoload colors zsh/terminfo
+if [[ "$terminfo[colors]" -ge 8 ]]; then
+  colors
+fi
+for color in RED GREEN YELLOW BLUE MAGENTA CYAN WHITE; do
+  eval PR_$color='%{$terminfo[bold]$fg[${(L)color}]%}'
+  eval PR_LIGHT_$color='%{$fg[${(L)color}]%}'
+done
+PR_NO_COLOR="%{$terminfo[sgr0]%}"
+
+# set variable identifying the chroot you work in (used in the prompt below)
+if [ -z "$debian_chroot" ] && [ -r /etc/debian_chroot ]; then
+  debian_chroot=$(cat /etc/debian_chroot)
+fi
+
+if [ "xlucid64" = "x$debian_chroot" ]; then
+    PS1="%n@$PR_GREEN% lucid64$PR_NO_COLOR %~ %#"
+else
+    PS1="%n@$PR_RED%m$PR_NO_COLOR %~ %#"
+fi
+```
+
+## Running X apps
+
+I also have `DISPLAY=:0` in my `$debian_chroot` section so I can run test\_shell or layout tests without manually setting my display every time.  Your display number may vary (`echo $DISPLAY` outside the chroot to see what your display number is).
+
+You can also use `Xvfb` if you only want to [run tests headless](http://code.google.com/p/chromium/wiki/LayoutTestsLinux#Using_an_embedded_X_server).
+
+## Having layout test results open in a browser
+
+After running layout tests, you should get a new browser tab or window that opens results.html.  If you get an error "Failed to open [file:///path/to/results.html](file:///path/to/results.html)", check the following conditions.
+
+  1. Make sure `DISPLAY` is set. See the [Running X apps](https://code.google.com/p/chromium/wiki/UsingALinuxChroot#Running_X_apps) section above.
+  1. Install `xdg-utils`, which includes `xdg-open`, a utility for finding the right application to open a file or URL with.
+  1. Install [Chrome](https://www.google.com/intl/en/chrome/browser/).