PHP script to backup a directory without use of exec or other system commands

I need a PHP script that can be used to compress and download public_html folder and all containing files using standard PHP functions. This script **HAS** to work on **PHP 5.1.6** and **configuration** included in project Detailed requirements. Please let me know if you need additional information. ## Deliverables This script **HAS** to work on **PHP 5.1.6** and following **configuration:** **Configure Command** './configure' '--build=i686-redhat-linux-gnu' '--host=i686-redhat-linux-gnu' '--target=i386-redhat-linux-gnu' '--program-prefix=' '--prefix=/usr' '--exec-prefix=/usr' '--bindir=/usr/bin' '--sbindir=/usr/sbin' '--sysconfdir=/etc' '--datadir=/usr/share' '--includedir=/usr/include' '--libdir=/usr/lib' '--libexecdir=/usr/libexec' '--localstatedir=/var' '--sharedstatedir=/usr/com' '--mandir=/usr/share/man' '--infodir=/usr/share/info' '--cache-file=../[login to view URL]' '--with-libdir=lib' '--with-config-file-path=/etc' '--with-config-file-scan-dir=/etc/php.d' '--disable-debug' '--with-pic' '--disable-rpath' '--without-pear' '--with-bz2' '--with-curl' '--with-exec-dir=/usr/bin' '--with-freetype-dir=/usr' '--with-png-dir=/usr' '--enable-gd-native-ttf' '--without-gdbm' '--with-gettext' '--with-gmp' '--with-iconv' '--with-jpeg-dir=/usr' '--with-openssl' '--with-png' '--with-pspell' '--with-expat-dir=/usr' '--with-pcre-regex=/usr' '--with-zlib' '--with-layout=GNU' '--enable-exif' '--enable-ftp' '--enable-magic-quotes' '--enable-sockets' '--enable-sysvsem' '--enable-sysvshm' '--enable-sysvmsg' '--enable-track-vars' '--enable-trans-sid' '--enable-yp' '--enable-wddx' '--with-kerberos' '--enable-ucd-snmp-hack' '--with-unixODBC=shared,/usr' '--enable-memory-limit' '--enable-shmop' '--enable-calendar' '--enable-dbx' '--enable-dio' '--with-mime-magic=/usr/share/file/[login to view URL]' '--without-sqlite' '--with-libxml-dir=/usr' '--with-xml' '--with-oci8=instantclient,/usr/lib/oracle/[login to view URL]' '--with-mcrypt' '--with-system-tzdata' '--with-apxs2=/usr/sbin/apxs' '--without-mysql' '--without-gd' '--without-odbc' '--disable-dom' '--disable-dba' '--without-unixODBC' '--disable-pdo' '--disable-xmlreader' '--disable-xmlwriter' **additional .ini files parsed** /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL], /etc/php.d/[login to view URL] **Loaded Modules ** core prefork http_core mod_so mod_auth_basic mod_auth_digest mod_authn_file mod_authn_alias mod_authn_anon mod_authn_dbm mod_authn_default mod_authz_host mod_authz_user mod_authz_owner mod_authz_groupfile mod_authz_dbm mod_authz_default util_ldap mod_authnz_ldap mod_include mod_log_config mod_logio mod_env mod_ext_filter mod_mime_magic mod_expires mod_deflate mod_headers mod_usertrack mod_setenvif mod_mime mod_dav mod_status mod_autoindex mod_info mod_dav_fs mod_vhost_alias mod_negotiation mod_dir mod_actions mod_speling mod_userdir mod_alias mod_rewrite mod_proxy mod_proxy_balancer mod_proxy_ftp mod_proxy_http mod_proxy_connect mod_cache mod_suexec mod_disk_cache mod_file_cache mod_mem_cache mod_cgi mod_authz_ldap mod_perl mod_php5 mod_proxy_ajp mod_python mod_apache mod_ssl mod_jrun22