$ curl -O http://pear.php.net/go-pear.phar
$ sudo php -d detect_unicode=0 go-pear.phar
Below is a suggested file layout for your new PEAR installation.  To
change individual locations, type the number in front of the
directory.  Type 'all' to change all of them or simply press Enter to
accept these locations.

 1. Installation base ($prefix)                   : /usr
 2. Temporary directory for processing            : /tmp/pear/install
 3. Temporary directory for downloads             : /tmp/pear/install
 4. Binaries directory                            : /usr/bin
 5. PHP code directory ($php_dir)                 : /usr/share/pear
 6. Documentation directory                       : /usr/docs
 7. Data directory                                : /usr/data
 8. User-modifiable configuration files directory : /usr/cfg
 9. Public Web Files directory                    : /usr/www
10. Tests directory                               : /usr/tests
11. Name of configuration file                    : /private/etc/pear.conf

1-11, 'all' or Enter to continue:   #ここではEnterを押しました
Unable to create PHP code directory ($php_dir) /usr/share/pear.
Run this script as root or pick another location.


$ sudo php /usr/lib/php/install-pear-nozlib.phar
Password:
[PEAR] Archive_Tar: failed to mkdir /usr/lib/php/pear/Archive
[PEAR] Console_Getopt: failed to mkdir /usr/lib/php/pear/Console
warning: pear/PEAR requires package "pear/Archive_Tar" (version >= 1.3.7)
warning: pear/PEAR requires package "pear/Structures_Graph" (recommended version 1.0.4)
warning: pear/PEAR requires package "pear/Console_Getopt" (recommended version 1.2.3)
warning: pear/PEAR requires package "pear/XML_Util" (recommended version 1.2.1)
[PEAR] PEAR: failed to mkdir /usr/lib/php/pear/OS
[PEAR] Structures_Graph: failed to mkdir /usr/lib/php/pear/docs/Structures_Graph/docs/html/media
[PEAR] XML_Util: failed to mkdir /usr/lib/php/pear/docs/XML_Util/examples