为什么为用户提供了用于PostgreSQL的外壳?
cat /etc/passwd |grep postgre postgres:x:115:127:PostgreSQL administrator,,,:/var/lib/postgresql:/bin/bash apt-cache show postgresql Package: postgresql Priority: optional Section: database Installed-Size: 65 Maintainer: Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com> Original-Maintainer: Debian PostgreSQL Maintainers <pkg-postgresql-public@lists.alioth.debian.org> Architecture: all Source: postgresql-common (136) Version: 9.1+136 Depends: postgresql-9.1 Filename: pool/main/p/postgresql-common/postgresql_9.1+136_all.deb Size: 5468 MD5sum: 34f5a1373ad5cd0b6f5aa3e7af06c9e7 SHA1: 6f271758bd51c23614b12fd63fb711ecfa43e9e5 SHA256: e8921a22b560e81f57a2a00001e31ba1036f67a8e7f151bf8f977b4919fc559a 我可以替换/bin/bash使用/bin/false?