On 28/08/2020 09:00 am, Gabriel Winkler wrote:
Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc -I/home/abuild/rpmbuild/BUILD/bash-4.4
-L/home/abuild/rpmbuild/BUILD/bash-4.4/../readline-7.0
Compilation CFLAGS: -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64'
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-suse-linux-gnu'
-DCONF_VENDOR='suse' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL
-DHAVE_CONFIG_H -I. -I. -I./include -I./lib -fmessage-length=0
-grecord-gcc-switches -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector-strong
-funwind-tables -fasynchronous-unwind-tables -fstack-clash-protection -g
-D_GNU_SOURCE -DRECYCLES_PIDS -Wall -g -Wuninitialized -Wextra -Wno-switch-enum
-Wno-unused-variable -Wno-unused-parameter -Wno-parentheses -ftree-loop-linear
-pipe -DBNC382214=0 -DIMPORT_FUNCTIONS_DEF=0 -fprofile-use -fprofile-correction
uname output: Linux sophie 4.12.14-150.32-default #1 SMP Thu Aug 1 08:42:52 UTC
2019 (a2a3983) x86_64 x86_64 x86_64 GNU/Linux
Machine Type: x86_64-suse-linux-gnu
Bash Version: 4.4
Patch Level: 23
Release Status: release
Description:
If I have a variable with the value 0 assigned to it incrementing it causes the
return code to be 1, even though the variable has been incremented
successfully. This only happens if the value of the variable is 0. With
positive and negative values this bug is no present.
Repeat-By:
# Works fine
test=1
((test++))
echo $?
0
echo $test
2
# Causes error
test=0
((test++))
echo $?
1
echo $test
1
Best Regards
Gabriel Winkler
_________________________
bpm consult ag
beeline solutions
Gabriel Winkler
DevOps Engineer
Industriestrasse Ost 10
CH-4614 Hägendorf
Telefon +41 61 417 10 68
Web www.bpm.ch<http://www.bpm.ch/>
From man bash:
((expression))
The expression is evaluated according to the rules described
below under ARITHMETIC EVALUATION. If the value of the
expression is non-zero, the return status is 0; otherwise the
return status is 1. This is exactly equivalent to
let "expression".
--
Chris Elvidge
England
