Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS: -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64'
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-pc-linux-gnu'
-DCONF_VENDOR='pc' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash'
-DSHELL -DHAVE_CONFIG_H -I. -I../. -I.././include -I.././lib
-Wdate-time -D_FORTIFY_SOURCE=2 -g -O2
-fdebug-prefix-map=/build/bash-N2nMjo/bash-4.4.18=.
-fstack-protector-strong -Wformat -Werror=format-security -Wall
-Wno-parentheses -Wno-format-security
uname output: Linux tau5vbub1 4.15.0-112-generic #113-Ubuntu SMP Thu Jul
9 23:41:39 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
Machine Type: x86_64-pc-linux-gnu
Bash Version: 4.4
Patch Level: 20
Release Status: release
Description:
'echo "$(<\"filename\")"' fails with No such file or directory
error.
'echo "$(cat \"filename\")"' also fails no such file or directory
error.
'echo "$(<filename)"' is okay.
'echo $(<"filename")' is okay.
I think I'm doing the nested double quoting correctly.
The quoting is because in my original case 'filename' was
a variable that could contained a filename with spaces in it.
My execution trace:
~ 19>cat fn
w1 w2
~ 20>echo $(<fn)
w1 w2
~ 21>echo $(<"fn")
w1 w2
~ 22>echo "$(<fn)"
w1 w2
~ 23>echo "$(<\"fn\")"
-bash: "fn": No such file or directory
Running "strace" shows that quote marks are not removed in
the failing case:
echo "$(<fn)":
[pid 3708] dup2(4, 1) = 1
[pid 3708] close(4) = 0
[pid 3708] close(3) = 0
[pid 3708] rt_sigprocmask(SIG_BLOCK, NULL, [], 8) = 0
>> [pid 3708] openat(AT_FDCWD, "fn", O_RDONLY) = 3
[pid 3708] read(3, "some text\n", 128) = 10
[pid 3708] write(1, "some text\n", 10 <unfinished ...>
[pid 3707] <... read resumed> "some text\n", 128) = 10
[pid 3708] <... write resumed> ) = 10
echo "$(<\"fn\")":
[pid 779] dup2(4, 1) = 1
[pid 779] close(4) = 0
[pid 779] close(3) = 0
[pid 779] rt_sigprocmask(SIG_BLOCK, NULL, [], 8) = 0
>> [pid 779] openat(AT_FDCWD, "\"fn\"", O_RDONLY) = -1 ENOENT
(No such file or di
[pid 779] openat(AT_FDCWD, "/usr/share/locale/locale.alias",
O_RDONLY|O_CLOEXE
[pid 779] fstat(3, {st_mode=S_IFREG|0644, st_size=2995, ...}) = 0
Repeat-By:
echo w1 w2 > filename
echo "$(<\"filename\")"
Fix:
[Description of how to fix the problem. If you don't know a
fix for the problem, don't include this section.]
