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-redhat-linux-gnu' -DCONF_VENDOR='redhat' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL -DHAVE_CONFIG_H -I. -I. -I./include -I./lib -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic uname output: Linux s1028505 3.10.0-957.10.1.el7.x86_64 #1 SMP Thu Feb 7 07:12:53 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux Machine Type: x86_64-redhat-linux-gnu
Bash Version: 4.2 Patch Level: 46 Release Status: release Description: When using arithmetic expansion with variable pre- and post-increments/decrements in the output redirection file path, specifically on external executables (not builtins or functions), the state of the variable being incremented/decremented is not persisted in the environment. Repeat-By: # n=1; true > $((--n)); echo $n; ls outputs: 0 0 but # n=1; /bin/true > $((--n)); echo $n; ls outputs: 1 0