First of all, I'm very new to programming.
I have a build a program using Xcode 4 on Snow Leopard.
Architecture of the project is set to "Standard (32/64-bit intel)"
Afterwards I have exported the executable file to a UNIX computer for running.
ssh to that computer
Typing ./programname in the terminal (Of the UNIX computer) gives the following response:
Exec format error. Wrong Architecture.
The program runs just fine on my Mac laptop.
When you compile a program it will (*) be compiled for a specific platform and a specific operating system. It will also most likely be compiled against a specific set of libraries. Usually those parameters are exactly those of the computer doing the compilation (the other cases are called cross-compilation).
In other words: compiling a program on a Mac will produce a binary that runs only on a Mac (unless, again, you're doing cross-compilation). Your UNIX system (which UNIX, by the way?) has a different operating system, different libraries and probably even a different CPU architetcture.
Somewhat related: Apples advertised (or used to advertise) Mac OS X as a UNIX. While Mac OS X is certainly a UNIX-class operating system, that doesn't mean that it's binary compatible with every other UNIX-class OS out there.
* almost always, with the exception of systems designed to avoid this (e.g. Java)
Programs compiled by XCode will only run under MacOS X. Unless the "UNIX computer" in step 2 is running MacOS, the program will not be able to run.
Related
I have one .bat script on my windows share that is mounted to my UNIX machine. Bat script is set to make file transfer between 2 windows shares, but I would like to trigger this script from a unix machine if that is possible. I was reading that you can do it with wine or dosbox, but I don't have that installed on my unix. Is it possible to resolve this problem with some additional .sh script that will trigger my .bat script correctly?
Thank you in advance.
Best regards.
You cannot run a .bat script on a Unix machine for several reasons :
Unix has not the same commands (on the command line) as Windows. The POSIX standard defined a set of commands, if you use them you'll be portable on various POSIX systems (but not on Windows); for example to list a directory, you'll use DIR on MSDOS and Windows but ls on Unix and POSIX; to copy a file it is COPY on MSDOS and Windows but cp on Unix and POSIX; etc....
Unix has not the same command interpreter as Windows. The POSIX standard and the Unix tradition provides a Unix shell and POSIX has standardized /bin/sh (a.k.a. POSIX shell). Windows has CMD (inherited from MSDOS) and PowerShell.
The way of interpreting commands is different (on Windows look also into PowerShell, which I don't know). On Unix it is the shell (not the invoked programs) that is expanding your command and globbing. See this answer for more. The notion of current working directory is different.
the operating system concepts are (slightly or significantly) different on Windows and on Unix or POSIX. For example, files, directories, processes, libraries are different (for example, a file can be written by a process and removed by another one on Unix and it can have several names on Linux thru hard links), .... etc.... You could read Operating Systems: Three Easy Pieces for an overview.
the Unix philosophy is not (always) applicable to Windows.
So you need to study Unix (or POSIX) and write your own shell script from scratch. Don't try to "translate" a bat script to a Unix shell script, but redesign it entirely (starting from the problem you want it to solve).
(and Wine or DosBox is not helpful in your case)
Read also about SCP and perhaps FTP. Perhaps using some distributed version control system like git could be relevant for you (e.g. to share scripts, source code, etc...).
If you need to run remotely some Windows .bat script on a distant Windows machine (e.g. from a Unix machine), you should use some remote command running service (that is, find and use some equivalent of SSH service on Windows, and use the corresponding client on Unix). See this.
So if you need to remotely run on a Windows server something (e.g. some program, some script, some command) from a Unix machine you should ask a different question (or at least improve a lot the current one).
Read about the client-server model and about application layer to use the correct terminology. You should name what protocol, server, client, service you want to involve. Nothing is magically "triggered" without using them.
PS. I'm using Unix since 1987, Linux since 1993. I never used Windows.
I want to know that if a shell script is created and tested on ubuntu kernel, then will it always without fail also run on RHEL kernel provided the correct shell is invoked for running the script.
Ways in which the execution may differ when used on different distributions and different kernels:
Differences in the version and configuration of the Linux kernel - this may affect presence and format of the contents of files such as those in /proc and /sys, or the presence of particular device drivers.
Differences in the version of the shell used - /bin/sh may be Bash on one system and Dash on another, or Bash 3.x on one system and Bash 4.x on the other.
Differences in the installed programs your script invokes (and, if you got your package dependencies wrong, whether those programs are even present - what's "essential" on one distribution may be "optional" on another).
In short, different distributions have the same issues as different versions of one distribution, but more so.
It depends on what shell/interpreter it was written for and versions of the particular shell it was written for. For example, a bash script written using bash-4.4 may not work in bash-2.0 and so on. It's not quite related to to the distribution/kernel version you use but the shell you use.
So, without details, it's not possible to assert whether a script that works on Ubuntu will work on RHEL. If you use the same shell and same version
on both machines then yes, it's going to work as expected (barring some very odd cases).
I had this question on my exam, now in diagrams I saw, we have : hardware, kernel, system call interface to the kernel, then (compilers, shells, sys.libs) and on top some applications. Does OS scope include only kernel, and everything else is just some additional functions we choose to install , or does a Unix OS include everything from the list I gave above?
OS have more or less 2 definitions :
academic : OS is soft for doing a abstraction layer between
hardware and software
pragmatic : OS is soft that come with hardware when we buy it.
Compiler and shell don't enter in definition 1. It can be enter in definition 2.
And usually, users that are interesting by a compiler or a shell prefer to consider OS as asbtraction layer (academic definition).
Simple answer, No. They are not an internal part of Unix but additional functionality to help make the Operating System more usable.
The OS scope applies primarily to the kernel only.
Whilst you need a compiler to build the kernel, you don't necessarily require one for the general day to day use of the system. Most operating systems don't ship the compiler by default and instead, the kernel and applications is built on one machine and then the resulting binarys are packaged and distributed either with the computer directly (Windows/Unix) or via the internet for others to download and install (Linux/BSD)
Likewise with the shell. Although all operating systems ship with a default one (sh/bash/dash on Linux|Unix systems, Command Prompt/Powershell on Windows), most general users can go their entire lives without using it.
Having said that, if you were to delete the shell, you'll almost certainly find your system won't boot up. This is because a lot of core start-up scripts rely on the shell to stop / start the services presenting interfaces between the user and the kernel.
In summary:
You need a compiler to build the kernel and applications but not for running the OS.
You need a shell to execute applications (which also includes the compiler)
I am trying to build a cross platform (vista, xp, mac, Linux).
I need to put the application in the USB drive formatted in FAT-32 and it should run on any OS computers.
Planning to use Java/JavaFx to do it.
Any advice how we can run on the multiple platforms.
Hi, Can anyone advice use of uber-jar for the above requirment. Would that be good fit.
A few things to take into consideration:
The USB must be formatted with a filesystem compatible with all the OS you need to work with.
A Java application would be able to run on any OS that is able to run Java, but each OS needs a different Java runtime. There's a Java runtime for Linux, one for Windows, one for OSX, etc.
My suggestion would be to define which OS you want to support and create launcher scripts for each one of them on the root of the USB. For instance you would have at least a couple like: myapp.cmd (for Windows), myapp.sh (for Linux), etc.
Additionally you may want to have different Java Runtimes in the same USB, so with the launcher scripts you execute your Java application running it with the corresponding JRE in the USB filesystem.
A twist in the launcher script would be to somehow check if the OS has already a JRE available (Like checking for a variable JAVA_HOME in the environment, or checking the output of "java -version") and act accordingly (although, running a Java application from your own JRE would be safer).
Is there some way to access the Windows version of a helpfile on a Linux computer within R?
I write a decent amount of R code on my Linux machine, but I do have to make sure the code will run on a Windows machine for collaborators.
I've been burned a number of times by reading a help file on my Linux machine, writing my code, and then spending hours wondering why it's not working on the Windows machine until I check the helpfile on that machine and realise that it is different to the one on the Linux machine.
It'll usually have a "NOTE: On Windows, xxxx behaves differently...", and I wish I knew that while I was writing the code on my Linux machine!
I do realise that many help files are system-specific (for example ?system), but sometimes I would like to read the Windows version on my Linux computer. Today I found myself wanting to read ?windows but had to boot up my Windows laptop just to read that helpfile, because that function isn't available on Linux and so there's no help file.
cheers.
You can always look at the source which gives you clear conditionals -- this is from man/system.Rd:
#ifdef windows
Only double quotes are allowed on Windows: see the examples. (Note: a
Windows path name cannot contain a double quote, so we do not need to
worry about escaping embedded quotes.)
[...]
#endif
#ifdef unix
Unix-alikes pass the command line to a shell (normally \file{/bin/sh},
and POSIX requires that shell), so \code{command} can be anything the
shell regards as executable, including shell scripts, and it can
contain multiple commands separated by \code{;}.
[...]
#endif