Shell

[Our shell gives the ability to view a user's shell info, execute simple commands, check if errors exist in commands, and run commands concurrently in the background. ]

Group Members

• Roderick Shaw: rks21b@fsu.edu
• Fernando Parra: fap20g@fsu.edu
• Sofia Sanchez: srs20h@fsu.edu

Division of Labor

BEFORE

Part 1: Prompt

• Responsibilities: [Print the user, machine, and path info from their envirnoment.]
• Assigned to: Roderick Shaw

Part 2: Environment Variables

• Responsibilities: [Parse all environment variables appropriately]
• Assigned to: Fernando Parra, Roderick Shaw, Sofia Sanchez

Part 3: Tilde Expansion

• Responsibilities: [Parse ~ as a home environment variable]
• Assigned to: Fernando Parra, Roderick Shaw, Sofia Sanchez

Part 4: $PATH Search

• Responsibilities: [Find proper paths for each command]
• Assigned to: Fernando Parra, Roderick Shaw, Sofia Sanchez

Part 5: External Command Execution

• Responsibilities: [Execute each command by forking them]
• Assigned to: Fernando Parra, Roderick Shaw, Sofia Sanchez

Part 6: I/O Redirection

• Responsibilities: [Allow execution functionally with files as input and output]
• Assigned to: Fernando Parra, Roderick Shaw, Sofia Sanchez

Part 7: Piping

• Responsibilities: [Allow piping execution]
• Assigned to: Fernando Parra, Roderick Shaw, Sofia Sanchez

Part 8: Background Processing

• Responsibilities: [Let commands run concurrently by executing commands w/ '&' in the background]
• Assigned to: Fernando Parra, Roderick Shaw, Sofia Sanchez

Part 9: Internal Command Execution

• Responsibilities: [Implement 3 commands: exit, cd PATH, and jobs]
• Assigned to: Fernando Parra, Roderick Shaw, Sofia Sanchez

Part 10: External Timeout Executable

• Responsibilities: [Implement mytimeout command]
• Assigned to: Fernando Parra, Roderick Shaw, Sofia Sanchez

Extra Credit

• Responsibilities: [Optional code if we have time to implement them]
• Assigned to: Nobody

AFTER

Part 1: Prompt

• Responsibilities: [Print the user, machine, and path info from their envirnoment.]
• Assigned to: Roderick Shaw, Fernando Parra

Part 2: Environment Variables

• Responsibilities: [Parse all environment variables appropriately]
• Assigned to: Fernando Parra

Part 3: Tilde Expansion

• Responsibilities: [Parse ~ as a home environment variable]
• Assigned to: Fernando Parra

Part 4: $PATH Search

• Responsibilities: [Find proper paths for each command]
• Assigned to: Sofia Sanchez

Part 5: External Command Execution

• Responsibilities: [Execute each command by forking them]
• Assigned to: Roderick Shaw

Part 6: I/O Redirection

• Responsibilities: [Allow execution functionally with files as input and output]
• Assigned to: Sofia Sanchez

Part 7: Piping

• Responsibilities: [Allow piping execution]
• Assigned to: Fernando Parra

Part 8: Background Processing

• Responsibilities: [Let commands run concurrently by executing commands w/ '&' in the background]
• Assigned to: Roderick Shaw

Part 9: Internal Command Execution

• Responsibilities: [Implement 3 commands: exit, cd PATH, and jobs]
• Assigned to: Fernando Parra

Part 10: External Timeout Executable

• Responsibilities: [Implement mytimeout command]
• Assigned to: Sofia Sanchez

Extra Credit

• Responsibilities: [Optional code if we have time to implement them]
• Assigned to: Fernando Parra

File Listing

shell/
│
├── src/
│ |── shell.c
│ |── bgProcessor.c
│ |── envirVar.c
│ |── mytimeout/
| |  └── mytimeout.c
│ |── ioRedirection.c
│ |── lexer.c
│ |── listOfCommands.c
│ |── pathSearch.c
│ |── piping.c
│ └── prompt.c
│
├── include/
│ |── lexer.h
| └── bgProcessor.h
│
├── README.md
└── Makefile

How to Compile & Execute

Requirements

• Compiler: gcc -std=c99 nameOfFile -o whatYouWantTheExecutableToBeNamed
• Dependencies: None needed to be downloaded

Compilation

make all

This will build both executables with the makefile and shoves the appropriate contents into the other folders in this directory. You must create the bin, obj, and obj2 folders in the same directory.

Execution

make run
./bin/shell

This will run the shell program and start off with a slightly different prompt than before. However, this will not create the mytimeout executable. Use make all and then bin/shell to get back into the shell executable.

Bugs

• Bug 1: Printing out commands in BGP isn't working properly.
• Bug 2: Piping doesn't seem to be going into the background.
• Bug 3: Exit doesn't always work (inconsistent)

Extra Credit

• Extra Credit 1: [Support unlimited number of pipes]
• Extra Credit 2: [Shell-ception]

Considerations

[Tilde expansion, external command execution, and internal commands are inside shell.c because they were too small for another file.]