79 lines
3.2 KiB
Text
79 lines
3.2 KiB
Text
|
This document details the incompatibilites between this version of bash,
|
||
|
|
bash-2.0, and the previous version, bash-1.14. These were discovered
|
||
|
|
by alpha and beta testers, so they will likely be encountered by a
|
||
|
|
significant number of users.
|
||
|
|
|
||
|
|
1. Bash now uses a new quoting syntax, $"...", to do locale-specific
|
||
|
|
string translation. Users who have relied on the (undocumented)
|
||
|
|
behavior of bash-1.14 will have to change their scripts. For
|
||
|
|
instance, if you are doing something like this to get the value of
|
||
|
|
a variable whose name is the value of a second variable:
|
||
|
|
|
||
|
|
eval var2=$"$var1"
|
||
|
|
|
||
|
|
you will have to change to a different syntax.
|
||
|
|
|
||
|
|
This capability is directly supported by bash-2.0:
|
||
|
|
|
||
|
|
var2=${!var1}
|
||
|
|
|
||
|
|
This alternate syntax will work portably between bash-1.14 and bash-2.0:
|
||
|
|
|
||
|
|
eval var2=\$${var1}
|
||
|
|
|
||
|
|
2. One of the bugs fixed in the YACC grammar tightens up the rules
|
||
|
|
concerning group commands ( {...} ). The `list' that composes the
|
||
|
|
body of the group command must be terminated by a newline or
|
||
|
|
semicolon. That's because the braces are reserved words, and are
|
||
|
|
recognized as such only when a reserved word is legal. This means
|
||
|
|
that while bash-1.14 accepted shell function definitions like this:
|
||
|
|
|
||
|
|
foo() { : }
|
||
|
|
|
||
|
|
bash-2.0 requires this:
|
||
|
|
|
||
|
|
foo() { :; }
|
||
|
|
|
||
|
|
This is also an issue for commands like this:
|
||
|
|
|
||
|
|
mkdir dir || { echo 'could not mkdir' ; exit 1; }
|
||
|
|
|
||
|
|
The syntax required by bash-2.0 is also accepted by bash-1.14.
|
||
|
|
|
||
|
|
3. The options to `bind' have changed to make them more consistent with
|
||
|
|
the rest of the bash builtins. If you are using `bind -d' to list
|
||
|
|
the readline keybindings in a form that can be re-read, use `bind -p'
|
||
|
|
instead. If you were using `bind -v' to list the keybindings, use
|
||
|
|
`bind -P' instead.
|
||
|
|
|
||
|
|
4. The `long' invocation options must now be prefixed by `--' instead
|
||
|
|
of `-'. (The old form is still accepted, for the time being.)
|
||
|
|
|
||
|
|
5. There was a bug in the version of readline distributed with bash-1.14
|
||
|
|
that caused it to write badly-formatted key bindings when using
|
||
|
|
`bind -d'. The only key sequences that were affected are C-\ (which
|
||
|
|
should appear as \C-\\ in a key binding) and C-" (which should appear
|
||
|
|
as \C-\"). If these key sequences appear in your inputrc, as, for
|
||
|
|
example,
|
||
|
|
|
||
|
|
"\C-\": self-insert
|
||
|
|
|
||
|
|
they will need to be changed to something like the following:
|
||
|
|
|
||
|
|
"\C-\\": self-insert
|
||
|
|
|
||
|
|
6. A number of people complained above having to use ESC to terminate an
|
||
|
|
incremental search, and asked for an alternate mechanism. Bash-2.0
|
||
|
|
allows ^J to terminate the search without accepting the line. Use
|
||
|
|
^M to terminate the search and accept the line, as in bash-1.14.
|
||
|
|
|
||
|
|
7. Some variables have been removed: MAIL_WARNING, notify, history_control,
|
||
|
|
command_oriented_history, glob_dot_filenames, allow_null_glob_expansion,
|
||
|
|
nolinks, hostname_completion_file, noclobber, no_exit_on_failed_exec, and
|
||
|
|
cdable_vars. Most of them are now implemented with the new `shopt'
|
||
|
|
builtin; others were already implemented by `set'.
|
||
|
|
|
||
|
|
8. The `ulimit' builtins now sets both hard and soft limits and reports the
|
||
|
|
soft limit by default (when neither -H nor -S is specified). This is
|
||
|
|
compatible with versions of sh and ksh that implement `ulimit'.
|