Command explanations : This switch builds static PAM libraries as well as the dynamic libraries. --with-mailspool=/var/mail: This switch makes the mailspool directory FHS compliant. : This switch lets the local administrator choose which configuration file setup to use. mv /lib/libpam.a /lib/libpam_misc.a /lib/libpamc.a /usr/lib: This command moves the static libraries to /usr/lib to comply with FHS.