My busybox does not execute non-applet utility commands - linux

I installed the latest busybox to my new embedded project. It runs OK until I try to put dropbear in my application. The busybox shell complains that dropbear is not found although "which dropbear" command gives me the correct answer "/sbin/dropbear". If I change its mode to RW, it complains that dropbear is not executable. I have tried other non-bosybox commands and it complains the same. It must be a setup issue. Can anyone help me out? Thank you very much.
Allan

Perhaps you're missing the necessary libraries? Some environments don't print helpful messages when this happens. Check what libraries it wants to link against.
ldd or objdump -x <file> |grep NEEDED are helpful.
You probably want to do this from your build machine, as it sounds like the embedded shell environment is pretty broken.

Eric Seppanen's answer is true,any missing dynamic library dependency will cause the cryptic "not found" message for the binary in question. Linux will also give this error if it cannot find ld-linux-x86-64.so.2 in the /lib64 directory, or for 32bit binaries, the corresponding 32bit ld-linux*.so in /lib.

Related

How to install Gnatcoll Postgres on Linux Centos 7

I have installed gprbuild, xmlada, and gnatcoll. I am now attempting to install gnatcoll_postgres. Which I have downladed from here: https://github.com/AdaCore/gnatcoll-db/
Within the Postgres folder is a Makefile, which I execute like so...
[parallels#localhost postgres]$ ls
gnatcoll_postgres.gpr gnatcoll-sql-postgres-gnade.ads
gnatcoll-sql-postgres.adb gnatcoll-sql-ranges.adb
gnatcoll-sql-postgres.ads gnatcoll-sql-ranges.ads
gnatcoll-sql-postgres-builder.adb Makefile
gnatcoll-sql-postgres-builder.ads postgres_support.c
gnatcoll-sql-postgres-gnade.adb README.md
[parallels#localhost postgres]$ make Makefile
which: no gnatls in (/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin:/var/lib/snapd/snap/bin:/home/parallels/.local/bin:/home/parallels/bin)
make: Nothing to be done for `Makefile'.
[parallels#localhost postgres]$
Would anybody please be able to tell me what this means...
which: no gnatls in (/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin:/var/lib/snapd/snap/bin:/home/parallels/.local/bin:/home/parallels/bin)
make: Nothing to be done for `Makefile'.
Any help would be greatly appreciated.
Please see the xmlada and gnatcoll in my project below, does this look like it's installed correctly? I'm presuming this isn't correct...
Thanks,
Lloyd
It means that your GNAT installation binaries aren’t on your PATH.
The README.txt from the adacore.com site says, in part,
To start using the tools in command-line mode, you will need to add
{install_prefix}/bin
to your PATH environment variable. Alternatively, you can simply launch
{install_prefix}/bin/gps
and GPS will automatically add itself to the PATH - it will also find the
cross compiler, if you have installed everything in the default locations.
Note that GPS will add this at the end of the PATH, meaning that it will find first any other GNAT installations that you have in your PATH.
I strongly suspect that you’ve been doing the latter, so that GPS adds itself (actually, of course, its own location) to the PATH, so that when it launches the compiler it finds the correct one.
When you run make from the terminal, the compiler isn’t on the PATH, so neither are gnatls, gprconfig, gprbuild and the rest of the GNAT tools.
What you need to do is to take the first choice from the README, and add /home/parallel/opt/GNAT/2019/bin to (the front of) your default PATH. How you do that depends on your shell.
You will find xmlada, gnatcoll already installed.

make: i686-linux-gnu-ld: Command not found

i want to install cpanm WWW::Curl::Form on my Synology NAS. But that fails. Here is the output cpanm WWW::Curl::Form WWW::Curl::Easy File::Find::Rule String::CRC32 URI::Escape
--> Working on WWW::Curl::Form
Fetching http://www.cpan.org/authors/id/S/SZ/SZBALINT/WWW-Curl-4.17.tar.gz ... OK
Configuring WWW-Curl-4.17 ... OK
Building and testing WWW-Curl-4.17 ... FAIL
! Installing WWW::Curl::Form failed. See /var/services/homes/fox/.cpanm/work/1541095458.25803/build.log
the log file gives me:
make: i686-linux-gnu-ld: Command not found
But i dont know how to fix it on my Synology NAS (DSM 6.2 and appollolake architecture DS918+)
After reviewing your additional comments, I believe I have potential solution. It looks like you are trying to install some Perl modules via the default Perl shell, cpan. As part of the installation process, the make utility is being executed. This utility is heavily used for compiling and building source from C and C++ source code, along with other languages.
The make utility is trying to call some executable i686-linux-gnu-ld which is a linker, see ld. A linker is a utility used in C programming for linking (combining) multiple compiled object files into a single executable binary. make is calling this utility as some sort of build process. Instead of calling i686-linux-gnu-ld it should probably just be calling ld. The only thing I am not sure about is why it is using the full name of the utility instead of ld.
I can think of two solutions. The first would be to update the make file to use the correct name for the linker. I'm not sure how you would do this when it is being installed via cpan since it is downloading a package and executing the make file before you have a chance to modify it. The other option is to create a symbolic link from the incorrect name and path of ld that the make file is using to the correct path /opt/bin/ld. This will result in ld being called when i686-linux-gnu-ld is called. Also, I forgot to mention it earlier but the which command will tell you where an executable / command is located on your shell's path.
The Stack Overflow post, How to symlink a file in Liunx?, gives a good explanation of how to create a symlink. You need to create a symlink to point to the correct name and path of the linker. To do so run the following command:
ln -s /opt/bin/ld /usr/bin/i686-linux-gnu-ld
Depending on the permissions of these directories you may need to run this command under a account with elevated permissions or via sudo. I apologize for this post being rather long and verbose. I just wanted to explain my solution in detail. I hope this helps. Please let me know if this doesn't resolve the problem.
edit: fixed typo in the command.

Cygwin Gcc error while loading shared libraries?

I have instaled Cygwin after running MinGW for a while now. But when I try to compile the console gives me:
/usr/lib/gcc/x86_64-pc-cygwin/4.9.2/cc1.exe: error while loading shared libraries: ?: cannot open shared object file: No such file or directory
What does this mean?
I have the same problem and I found the solution.
According to the FAQ of Cygwin
Q: Why is C:\cygwin\usr\bin invisible from windows?
A: Because it does not really exist. In cygwin, /usr/bin is just a link to /bin.
So trying to add "C:\cygwin\usr\bin" to PATH will be in vain.
Add "C:\cygwin64\bin" to PATH instead. Hope this helps :)
You are missing a library, please run cygcheck /usr/lib/gcc/x86_64-pc-cygwin/4.9.2/cc1.exe or ldd /usr/lib/gcc/x86_64-pc-cygwin/4.9.2/cc1.exe to see what is the missing library.
(I'd rather ask a question in the comments first, but I don't have enough reputation yet.)
Your cc1 is unable to load some DLLs it needs to start. Looking at the Cygwin source code, this can be either a library specified in LD_PRELOAD, or -- more probably -- a library the executable depends on. The ? in the error message seems to be the default return value of find_first_notloaded_dll (hookapi.cc), in case the function can't determine what library is missing.
To diagnose the issue, I suggest checking your PATH variable (or even clearing it of any non-Cygwin paths and trying the compilation again) and/or using Dependency Walker to find the missing DLLs (start it from a Cygwin shell, so it can see the same PATH). ldd (included with Cygwin) may also give some clues, but I wouldn't bet on it.
It's possible a clean re-install of Cygwin will be necessary to solve the issue.
Most likely, you are simply missing /usr/bin in the PATH variable.
Adding 'export PATH=/usr/bin:$PATH' to your .bashrc file will solve the issue.
Adding some background info. I had the same problem when building my own program and linking it against graphviz cgraph.dll. Turns out this is related to where windows searches for DLLs (see here: https://msdn.microsoft.com/en-us/library/7d83bc18.aspx) So adding the path of your missing library to PATH should fix the problem.
It is unfortunate that the message doesn't include the name of the library. Luckily cmd.exe DOES give you this name (so it's good for something after all;)
Are you including the path to your lib directory?
Looks like you are not
I'm not very familiar with Cygwin, I mainly use MinGW, but I think the error message speaks for itself
I also came this error on windows machine while executing .exe file generated by scilab2C i.e toolbox for Scilab
For Windows 32 bit Add the environment variable path as follow :
C:\cygwin\usr\i686-pc-cygwin\bin
Hope so this will solve your issue.
Just had this problem trying to compile a package with make and it wanted some cygguile dll file that was just installed along with make.
My solution was I had not only migrated my cygwin64 directory across drives because the sector sizes were mismatched for some reason even though the drivers were both under 2TB and should have been using 512 byte sector sizes.. So I had to install a new system and move files over there, might have had weird permissions on them.
Also had to patch cygwin1.dll end of Jan 2020 because of a recent input problem in ConEmu with Windows 10 1903 build, but just did it again with this working so that doesn't seem to be the issue.
Reinstalling cygwin by deleting that entire directory, taking ownership of it first.., seemed to work now...

Linux binary can't find shared library, but works while running in strace

(Note: names of the binary and binary and library below are obfuscated to protect the innocent. ;-) The app is proprietary under NDA but the behavior may not depend on it.)
I have a Linux binary which prints the following error when run:
binary: error while loading shared libraries: libshared.so: cannot open shared object file: No such file or directory
Which is confusing on its own since libshared.so is in the LD_LIBRARY_PATH. However,
The library is found correctly when running ldd binary (i.e., the ldd output points to the file location)
The library is found correctly when running strace binary, so that the program manages to print its usage information!
I have never seen an application which behaves differently when run on its own vs in strace, but I figure maybe someone else has seen this happen before? Any ideas how to resolve this?
I don't have the source so I can't rebuild. Running the app in production under strace is probably a non-starter. The OS is RHEL 6.2.
(Old question, but hopefully this will help somebody else)
Under new Linux installations, LD_LIBRARY_PATH is not used by the standard system runtime linker for programs with SUID set. It appears that strace, gdb and friends work differently, and do use LD_LIBRARY_PATH.
For suid programs, all libraries must be found in the system library cache. Check (as root) whether your "missing" library is present using
ldconfig -p | grep <my_library_name>
and, if anything's missing, add it to a new file in /etc/ld.so.conf or ld.so.conf.d/ as appropriate, and then rebuild using
ldconfig -v
Or remove the SUID bit if it's not required, of course.
This really helped me a lot!
I was having a similar problem where libraries were not being picked up properly from the LD_LIBRARY_PATH, even when the ldd command showed all libraries were satisfied. However, when troubleshooting using strace, it was working. In my case, however, the problem was that SGID (set group ID sticky bit being on). When the files were installed, the sysadmin did a recursive chmod that set it on all files (including the executables). Once the SGID was removed on the executables, the libraries were now found without strace and everything worked as it should using the LD_LIBRARY_PATH.

make: pwd: Command not found

I am new to using make files. I have cygwin and MinGW. I'm still looking into their differences.
Anyway, I have a makefile that is used to create a project for an FPGA, which I have never done before. I have included C:\cygwin\bin and C:\MinGW\msys\1.0\bin in my PATH, but I always get this error.
make: pwd: Command not found
I typed pwd into the cmd prompt and get a correct response. Any pointers? Am I missing something? Not sure what else I can try. Most forums I have found pertaining to this error never have a resolution.
Let me know what information you'd like.
pwd is commonly both a shell built-in command and a standalone executable, provided by GNU coreutils (which Cygwin installs by default).
If you're invoking make from the Cygwin environment (say, typing make at a bash shell prompt), then C:\cygwin\bin is the wrong way to specify the directory. That's the path as seen from Windows. From within Cygwin, it's /bin -- and it should be in your default $PATH. The Cygwin equivalent of C:\MinGW\msys\1.0\bin would be /cygdrive/c/mingw/msys/1.0/bin
If you're doing this directly from Windows rather than in the Cygwin subsystem, then C:\cygwin\bin is the path to the Cygwin bin directory -- but running C:\cygwin\bin\pwd is going to give you a Cygwin-specific directory name that's not going to be meaningful to Windows.
I have encountered the same issue in my mingw environment. It turned out in my case to be a missing 'pwd'executable in the msys/bin directory. Once the copying was done properly, everything fell into place. Hope this helps

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