Shell Command Language Index

Shell Command Language

Shell Introduction

Quoting

· Escape Character (Backslash) · Single-quotes · Double-quotes

Token Recognition

· Alias Substitution

Reserved Words

Parameters and Variables

· Positional Parameters · Special Parameters · Shell Variables

Word Expansions

· Tilde Expansion · Parameter Expansion · Examples · Command Substitution · Arithmetic Expansion · Field Splitting · Pathname Expansion · Quote Removal

Redirection

· Redirecting Input · Redirecting Output · Appending Redirected Output · Here-document · Duplicating an Input File Descriptor · Duplicating an Output File Descriptor · Open File Descriptors for Reading and Writing

Exit Status and Errors

· Consequences of Shell Errors · Exit Status for Commands

Shell Commands

· Simple Commands · Command Search and Execution · Pipelines · Exit Status · Lists · Asynchronous Lists · Sequential Lists · AND Lists · OR Lists · Compound Commands · Grouping Commands · For Loop · Case Conditional Construct · If Conditional Construct · While Loop · Until Loop · Function Definition Command · Exit Status

Shell Grammar

· Shell Grammar Lexical Conventions · Shell Grammar Rules

Signals and Error Handling

Shell Execution Environment

Pattern Matching Notation

· Patterns Matching a Single Character · Patterns Matching Multiple Characters · Patterns Used for Filename Expansion

Special Built-in Utilities

· break - Exit From for, while or until Loop · colon - Null Utility · continue - Continue for, while or until Loop · dot - Execute Commands in Current Environment · eval - Construct Command by Concatenating Arguments · exec - Execute Commands and Open, Close or Copy File Descriptors · exit - Cause the Shell to Exit · export - Set Export Attribute for Variables · readonly - Set Read-only Attribute for Variables · return - Return from a Function · set - Set or Unset Options and Positional Parameters · shift - Shift Positional Parameters · times - Write Process Times · trap - Trap Signals · unset - Unset Values and Attributes of Variables and Functions