Imported from ../bash-2.01.1.tar.gz.

[thirdparty/bash.git] / NOTES

Platform-Specific Configuration and Operation Notes
===================================================

1.  configure --without-gnu-malloc on:

	alpha running OSF/1
	alpha running Linux

	next running NeXT/OS

	all machines running SunOS YP code: SunOS4, SunOS5, HP/UX

	linux (optional, but don't do it if you're using Doug Lea's malloc)

	QNX 4.2
	other OSF/1 machines (KSR/1, HP, IBM AIX/ESA)
	AIX
	sparc SVR4, SVR4.2 (ICL reference port)
	DG/UX
	Cray

	NetBSD/sparc (malloc needs 8-byte alignment; GNU malloc has 4-byte)

	BSD/OS 2.1 if you want to use loadable builtins

	If you are using GNU libc, especially on a linux system

(Configuring --without-gnu-malloc will still result in lib/malloc/libmalloc.a
being built and linked against, but there is only a stub file in the archive.)

2.  configure using shlicc on BSD/OS 2.1 to use loadable builtins

3.  Bash cannot be built in a directory separate from the source directory
    using configure --srcdir=... unless the version of `make' you're using
    does $VPATH handling right.  The script support/mkclone can be used to
    create a `build tree' using symlinks to get around this.

4.  I've had reports that username completion (as well as tilde expansion
    and \u prompt expansion) does not work on IRIX 5.3 when linking with
    -lnsl.  This is only a problem when you're running NIS, since
    apparently -lnsl supports only /etc/passwd and not the NIS functions
    for retrieving usernames and passwords.  Editing the Makefile after
    configure runs and removing the `-lnsl' from the assignment to `LIBS'
    fixes the problem.

5.  There is a problem with Red Hat Linux's `makewhatis' script.
    Running `makewhatis' with bash-2.0 results in error messages
    like this:

    /usr/sbin/makewhatis: cd: manpath: No such file or directory
    /usr/sbin/makewhatis: manpath/whatis: No such file or directory
    chmod: manpath/whatis: No such file or directory
    /usr/sbin/makewhatis: cd: catpath: No such file or directory
    /usr/sbin/makewhatis: catpath/whatis: No such file or directory
    chmod: catpath/whatis: No such file or directory

    The problem is with `makewhatis'.  Red Hat (and possibly other
    Linux distributors) uses a construct like this in the code:

        eval path=$"$pages"path

    to do indirect variable expansion.  This `happened to work' in
    bash-1.14 and previous versions, but that was more an accident
    of implementation than anything else -- it was never supported
    and certainly is not portable.

    Bash-2.0 has a new feature that gives a new meaning to $"...".
    This is explained more completely in item 1 in the COMPAT file.

    The three lines in the `makewhatis' script that need to be changed
    look like this:

             eval $topath=$"$topath":$name
    [...]
       eval path=$"$pages"path
    [...]
    eval path=$"$pages"path

    The portable way to write this code is

             eval $topath="\$$topath":$name
       eval path="\$$pages"path
    eval path="\$$pages"path

    You could also experiment with another new bash feature: ${!var}.
    This does indirect variable expansion, making the use of eval
    unnecessary.

6.  There is a problem with syslogd on many Linux distributions (Red Hat
    and Slackware are two that I have received reports about).  syslogd
    sends a SIGINT to its parent process, which is waiting for the daemon
    to finish its initialization.  The parent process then dies due to
    the SIGINT, and bash reports it, causing unexpected console output
    while the system is booting that looks something like

	starting daemons: syslogd/etc/rc.d/rc.M: line 29: 38 Interrupt ${NET}/syslogd

    Bash-2.0 reports events such as processes dying in scripts due to
    signals when the standard output is a tty.  Bash-1.14.x and previous
    versions did not report such events.

    This should probably be reported as a bug to whatever Linux distributor
    people see the problem on.  In my opinion, syslogd should be changed to
    use some other method of communication, or the wrapper function (which
    appeared to be `daemon' when I looked at it some time ago) or script
    (which appeared to be `syslog') should catch SIGINT, since it's an
    expected event, and exit cleanly.

7.  Several people have reported that `dip' (a program for SLIP/PPP
    on Linux) does not work with bash-2.0 installed as /bin/sh.

    I don't run any Linux boxes myself, and do not have the dip
    code handy to look at, but the `problem' with bash-2.0, as
    it has been related to me, is that bash requires the `-p'
    option to be supplied at invocation if it is to run setuid
    or setgid. 

    This means, among other things, that setuid or setgid programs
    which call system(3) (a horrendously bad practice in any case)
    relinquish their setuid/setgid status in the child that's forked
    to execute /bin/sh. 

    The following is an *unofficial* patch to bash-2.0 that causes it
    to not require `-p' to run setuid or setgid if invoked as `sh'.
    It has been reported to work on Linux.  It will make your system
    vulnerable to bogus system(3) calls in setuid executables.

--- ../bash-2.0.orig/shell.c    Wed Dec 18 14:16:30 1996
+++ shell.c     Fri Mar  7 13:12:03 1997
@@ -347,7 +347,7 @@
   if (posixly_correct)
     posix_initialize (posixly_correct);

-  if (running_setuid && privileged_mode == 0)
+  if (running_setuid && privileged_mode == 0 && act_like_sh == 0)
     disable_priv_mode ();

   /* Need to get the argument to a -c option processed in the