Configuration Information [Automatically generated, do not change]:
Machine: i686
OS: cygwin
Compiler: gcc-4
Compilation CFLAGS: -DPROGRAM='bash.exe' -DCONF_HOSTTYPE='i686'
-DCONF_OSTYPE='cygwin' -DCONF_MACHTYPE='i686-pc-cygwin'
-DCONF_VENDOR='pc' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash'
-DSHELL -DHAVE_CONFIG_H -DRECYCLES_PIDS -I.
-I/usr/src/bash-3.2.49-23/src/bash-3.2
-I/usr/src/bash-3.2.49-23/src/bash-3.2/include
-I/usr/src/bash-3.2.49-23/src/bash-3.2/lib -O2 -pipe
uname output: CYGWIN_NT-5.1 universi-c1eec2 1.7.0(0.218/5/3)
2009-12-04 17:08 i686 Cygwin
Machine Type: i686-pc-cygwin
Bash Version: 3.2
Patch Level: 49
Release Status: release
Description:
This bug report against the Bash Reference Manual stems from a discussion
on bug-bash [1].
The Bash Reference Manual's description of Shell Operation [2] omits
from its description of tokenization (Step 2) that the shell must
recognize expansion constructs.
Step 2 says:
[The shell] breaks the input into words and operators, obeying the
quoting rules described in Quoting. These tokens are separated by
metacharacters. Alias expansion is performed by this step (see
Aliases).
Applying this tokenization description to a simple example:
[...@host ~] $ echo The date is $(date +"%Y-%m-%d")
would result in this list of tokens:
------- -------------
echo word
<space> metacharacter
The word
<space> metacharacter
date word
<space> metacharacter
is word
<space> metacharacter
$ word
( metacharacter
date word
<space> metacharacter
+"%Y-%m-%d" word
) metacharacter
A reading of POSIX re Shell Token Recognition [3] indicates that shell
tokenization respects substitution candidates intact. The list of tokens
is the simple example then become:
------------------- -------------
echo word
<space> metacharacter
The word
<space> metacharacter
date word
<space> metacharacter
is word
<space> metacharacter
$(date +"%Y-%m-%d") word
[1] http://thread.gmane.org/gmane.comp.shells.bash.bugs/14377
or
http://lists.gnu.org/archive/html/bug-bash/2010-02/msg00119.html
[2] http://www.gnu.org/software/bash/manual/bashref.html#Shell-Operation
[3]
http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_03
Repeat-By:
Fix:
I recommend that the first sentence of Step 2 be appended with the
following:
"and keeping intact sequences of characters comprising expansions (see
Shell Expansions)."
Allen
--
Allen Halsey
