C code Please write C please write instruction how to run code as well I need makefile Here is one solution but it's in C I need C solution link https github com Dfaults simple shell myshell Basic Shell myshell Your basic shell, called myshell is basically an interactive loop it repeatedly prints a prompt myshell (note the space after the greater than sign), parses the input, executes the command specified on that line of input, and waits for the command to finish This is repeated until the user types exit The name of your final executable should be myshell The shell can be invoked with either no arguments or a single argument anything else is an error Here is the no argument way Page 1 of 10 prompt myshell myshell At this point, myshell is running, and ready to accept commands Type away The mode above is called interactive mode, and allows the user to type commands directly The shell also supports a batch mode, which instead reads input from a batch file and executes commands from therein Here is how you run the shell with a batch file named batch txt prompt myshell batch txt One difference between batch and interactive modes in interactive mode, a prompt is printed (myshell ) In batch mode, no prompt should be printed You should structure your shell such that it creates a process for each new command (the exception are built in commands, discussed below) Your basic shell should be able to parse a command and run the program corresponding to the command For example, if the user types ls la tmp, your shell should run the program bin ls with the given arguments la and tmp (how does the shell know to run bin ls It's something called the shell path more on this below) Your project is to develop write a simple shell myshell that has the following properties 1 The shell must support the following internal commands a cd Change the current default directory to If the argument is not present, report the current directory If the directory does not exist an appropriate error should be reported This command should also change the PWD environment variable clr Clear the screen dir List the contents of directory environ List all the environment strings echo Display on the display followed by a new line (multiple spaces tabs may be reduced to a single space) help Display the user manual using the more filter pause Pause operation of the shell until 'Enter' is pressed quit Quit the shell The shell environment should contain shell myshell where myshell is the Page 2 of 10 2 3 full path for the shell executable(not a hardwired path back to your directory, but the one from which it was executed) All other command line input is interpreted as program invocation, which should be done by the shell forking and execing the programs as its own child processes The programs should be executed with an environment that contains the entry parent myshell where myshell is as described in 1 i above The shell must be able to take its command line input from a file That is, if the shell is invoked with a command line argument myshell batchfile then batchfile is assumed to contain a set of command lines for the shell to process When the end of file is reached, the shell should exit Obviously, if the shell is invoked without a command line argument, it solicits input from the user via a prompt on the display 4 The shell must support I O redirection on either or both stdin and or stdout That is, the command line programname arg1 arg2 inputfile outputfile will execute the program programname with arguments arg1 and arg2, the stdin FILE stream replaced by inputfile and the stdout FILE stream replaced by outputfile stdout redirection should also be possible for the internal commands dir, environ, echo, help With output redirection, if the redirection character is then the outputfile is created if it does not exist and truncated if it does If the redirection token is then outputfile is created if it does not exist and appended to if it does 5 The shell must support background execution of programs An ampersand ( ) at the end of the command line indicates that the shell should return to the command line prompt immediately after launching that program Page 3 of 10 6 You are to include an implementation of command line pipes (essentially an extension of redirection) so that commands can be strung together An example is cat out txt wc l 7 The command line prompt must contain the pathname of the current directory Note You can assume that all command line arguments (including the redirection symbols, and the background execution symbol, ) will be delimited from other command line arguments by white space one or more spaces and or tabs (see the command line in 4 above)

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C++ code Please write C++. please write instruction how to run code as well. I need makefile Here is one solution but it's in C.

C++ code

Please write C++. please write instruction how to run code as well. I need makefile

Here is one solution but it's in C. I need C++

solution link: https://github.com/Dfaults/simple-shell---myshell--

Basic Shell: myshell Your basic shell, called myshell is basically an interactive loop: it repeatedly

prints a prompt myshell> (note the space after the greater-than sign), parses the input, executes the command specified on that line of input, and waits for the command to finish. This is repeated until the user types exit. The name of your final executable should be myshell. The shell can be invoked with either no arguments or a single argument; anything else is an error. Here is the no-argument way:

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prompt> ./myshell myshell>

At this point, myshell is running, and ready to accept commands. Type away!

The mode above is called interactive mode, and allows the user to type commands directly. The shell also supports a batch mode, which instead reads input from a batch file and executes commands from therein. Here is how you run the shell with a batch file named batch.txt:

prompt> ./myshell batch.txt

One difference between batch and interactive modes: in interactive mode, a prompt is printed (myshell> ). In batch mode, no prompt should be printed. You should structure your shell such that it creates a process for each new command (the exception are built-in commands, discussed below). Your basic shell should be able to parse a command and run the program corresponding to the command. For example, if the user types ls -la /tmp, your shell should run the program /bin/ls with the given arguments

-la and /tmp (how does the shell know to run /bin/ls? It's something called the shell path; more on this below).

Your project is to develop/write a simple shell - myshell - that has the following properties:

1. The shell must support the following internal commands:

a. cd - Change the current default directory to . If the argument is not present, report the current directory. If the directory does not exist an appropriate error should be reported. This command should also change the PWD environment variable.

clr - Clear the screen.
dir - List the contents of directory

.
environ - List all the environment strings.

echo - Display on the display followed

 by a new line (multiple spaces/tabs may be reduced to a

single space).

help - Display the user manual using the more filter.
pause - Pause operation of the shell until 'Enter' is

pressed.
quit - Quit the shell.
The shell environment should contain

shell=/myshell where /myshell is the

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full path for the shell executable(not a hardwired path back to your directory, but the one from which it was executed).

All other command line input is interpreted as program invocation, which should be done by the shell forking and execing the programs as its own child processes. The programs should be executed with an environment that contains the entry: parent=/myshell where /myshell is as described in 1.i. above.

The shell must be able to take its command line input from a file. That is, if the shell is invoked with a command line argument:

 myshell batchfile

then batchfile is assumed to contain a set of command lines for the shell to process. When the end-of-file is reached, the shell should exit. Obviously, if the shell is invoked without a command line argument, it solicits input from the user via a prompt on the display.

4. The shell must support I/O - redirection on either or both stdin and/or stdout. That is, the command line

 programname arg1 arg2 < inputfile > outputfile

will execute the program programname with arguments arg1 and arg2, the stdin FILE stream replaced by inputfile and the stdout FILE stream replaced by outputfile.

stdout redirection should also be possible for the internal commands dir, environ, echo, & help.

With output redirection, if the redirection character is > then the outputfile is created if it does not exist and truncated if it does. If the redirection token is >> then outputfile is created if it does not exist and appended to if it does.

5. The shell must support background execution of programs. An ampersand (&) at the end of the command line indicates that the shell should return to the command line prompt immediately after launching that program.

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6. You are to include an implementation of command line pipes. (essentially an extension of redirection) so that commands can be strung together. An example is

cat out.txt | wc l

7. The command line prompt must contain the pathname of the current directory.

Note: You can assume that all command line arguments (including the redirection symbols, <, > & >> and the background execution symbol, &) will be delimited from other command line arguments by white space - one or more spaces and/or tabs (see the command line in 4. above).