Via phpinfo, I get the following for include_path Master Value.
.:/usr/share/pear:/usr/share/php
It does not appear to be set anywhere... php ini has all include_path(s) commented out, my apps do not set it manually, apache conf/php conf/other assorted conf's/ini's do not set it, no results when searching for set_include_path or phpvalue or ini_set, etc.
Any ideas where else "include_path" might be set? I am asking specifically about master value.
(I am on CentOS 5.4)
It's configured at build time. You can see how your PHP installation was configured by looking at the Configure Command in the output from phpinfo();
For more information on PHP configure options see PHP Installation and Configuration. Also php-build — Builds multiple versions of PHP might be of help or interest.
You won't find the configure command in the phpinfo output, see this bug marked as invalid. Here are some links to code mentioned in the bug report.
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=../config.cache' '--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/magic.mime' '--without-sqlite' '--with-libxml-dir=/usr' '--with-xml' '--with-system-tzdata' '--enable-force-cgi-redirect' '--enable-pcntl' '--with-imap=shared' '--with-imap-ssl' '--enable-mbstring=shared' '--enable-mbstr-enc-trans' '--enable-mbregex' '--with-ncurses=shared' '--with-gd=shared' '--enable-bcmath=shared' '--enable-dba=shared' '--with-db4=/usr' '--with-xmlrpc=shared' '--with-ldap=shared' '--with-ldap-sasl' '--with-mysql=shared,/usr' '--with-mysqli=shared,/usr/lib/mysql/mysql_config' '--enable-dom=shared' '--with-dom-xslt=/usr' '--with-dom-exslt=/usr' '--with-pgsql=shared' '--with-snmp=shared,/usr' '--enable-soap=shared' '--with-xsl=shared,/usr' '--enable-xmlreader=shared' '--enable-xmlwriter=shared' '--enable-fastcgi' '--enable-pdo=shared' '--with-pdo-odbc=shared,unixODBC,/usr' '--with-pdo-mysql=shared,/usr/lib/mysql/mysql_config' '--with-pdo-pgsql=shared,/usr' '--with-pdo-sqlite=shared,/usr' '--enable-dbase=shared'