Hi, In recent Linux distributions, we have at least the following packages that write to /etc/passwd: 1. pwdb (provides libpwdb, which is used by pam_pwdb). 2. pam_unix (included with Linux-PAM). 3. util-linux (provides chsh, chfn). 4. shadow-utils (provides useradd and the like). Only #1 and #4 use compatible locking. All of these are found on at least RH 6.x. pam_unix isn't used by default, but is often recommended on pam-list and apparently is going to replace pam_pwdb in RH 7.x. Solutions? 1. Move to a more consistent system. Bonus: consistent man pages. 2. Patch util-linux, patch pam_unix. 3. Patch util-linux, don't use pam_unix. 4. Use the versions of chsh and chfn provided with shadow-utils rather than ones provided with util-linux (any particular reason RH prefers the util-linux versions?). Don't use pam_unix. Signed, Solar Designer
