User Search

Introduction

In this challenge, we will write a script to search for a user present in the system. We will fetch the usernames from the /etc/passwd file and search for the given name in the list. This challenge will help us understand how to work with configuration files and how to search for a specific string in a file using shell scripting.

Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL shell(("`Shell`")) -.-> shell/ControlFlowGroup(["`Control Flow`"]) linux(("`Linux`")) -.-> linux/BasicFileOperationsGroup(["`Basic File Operations`"]) linux(("`Linux`")) -.-> linux/BasicSystemCommandsGroup(["`Basic System Commands`"]) linux(("`Linux`")) -.-> linux/InputandOutputRedirectionGroup(["`Input and Output Redirection`"]) linux(("`Linux`")) -.-> linux/UserandGroupManagementGroup(["`User and Group Management`"]) linux(("`Linux`")) -.-> linux/SystemInformationandMonitoringGroup(["`System Information and Monitoring`"]) shell(("`Shell`")) -.-> shell/BasicSyntaxandStructureGroup(["`Basic Syntax and Structure`"]) shell(("`Shell`")) -.-> shell/VariableHandlingGroup(["`Variable Handling`"]) shell(("`Shell`")) -.-> shell/FunctionsandScopeGroup(["`Functions and Scope`"]) shell(("`Shell`")) -.-> shell/AdvancedScriptingConceptsGroup(["`Advanced Scripting Concepts`"]) shell(("`Shell`")) -.-> shell/SystemInteractionandConfigurationGroup(["`System Interaction and Configuration`"]) shell/ControlFlowGroup -.-> shell/if_else("`If-Else Statements`") linux/BasicFileOperationsGroup -.-> linux/cat("`File Concatenating`") linux/BasicFileOperationsGroup -.-> linux/cut("`Text Cutting`") linux/BasicSystemCommandsGroup -.-> linux/exit("`Shell Exiting`") linux/BasicSystemCommandsGroup -.-> linux/echo("`Text Display`") linux/InputandOutputRedirectionGroup -.-> linux/pipeline("`Data Piping`") linux/InputandOutputRedirectionGroup -.-> linux/redirect("`I/O Redirecting`") linux/BasicSystemCommandsGroup -.-> linux/read("`Input Reading`") linux/UserandGroupManagementGroup -.-> linux/passwd("`Password Changing`") linux/SystemInformationandMonitoringGroup -.-> linux/df("`Disk Space Reporting`") shell/BasicSyntaxandStructureGroup -.-> shell/shebang("`Shebang`") shell/BasicSyntaxandStructureGroup -.-> shell/comments("`Comments`") shell/BasicSyntaxandStructureGroup -.-> shell/quoting("`Quoting Mechanisms`") shell/VariableHandlingGroup -.-> shell/variables_decl("`Variable Declaration`") shell/VariableHandlingGroup -.-> shell/variables_usage("`Variable Usage`") shell/VariableHandlingGroup -.-> shell/str_manipulation("`String Manipulation`") shell/VariableHandlingGroup -.-> shell/arrays("`Arrays`") shell/VariableHandlingGroup -.-> shell/param_expansion("`Parameter Expansion`") shell/ControlFlowGroup -.-> shell/for_loops("`For Loops`") shell/ControlFlowGroup -.-> shell/cond_expr("`Conditional Expressions`") shell/ControlFlowGroup -.-> shell/exit_status("`Exit and Return Status`") shell/FunctionsandScopeGroup -.-> shell/func_def("`Function Definition`") shell/AdvancedScriptingConceptsGroup -.-> shell/arith_expansion("`Arithmetic Expansion`") shell/AdvancedScriptingConceptsGroup -.-> shell/read_input("`Reading Input`") shell/AdvancedScriptingConceptsGroup -.-> shell/cmd_substitution("`Command Substitution`") shell/AdvancedScriptingConceptsGroup -.-> shell/subshells("`Subshells and Command Groups`") shell/SystemInteractionandConfigurationGroup -.-> shell/globbing_expansion("`Globbing and Pathname Expansion`") subgraph Lab Skills shell/if_else -.-> lab-18277{{"`Search User in System Configuration`"}} linux/cat -.-> lab-18277{{"`Search User in System Configuration`"}} linux/cut -.-> lab-18277{{"`Search User in System Configuration`"}} linux/exit -.-> lab-18277{{"`Search User in System Configuration`"}} linux/echo -.-> lab-18277{{"`Search User in System Configuration`"}} linux/pipeline -.-> lab-18277{{"`Search User in System Configuration`"}} linux/redirect -.-> lab-18277{{"`Search User in System Configuration`"}} linux/read -.-> lab-18277{{"`Search User in System Configuration`"}} linux/passwd -.-> lab-18277{{"`Search User in System Configuration`"}} linux/df -.-> lab-18277{{"`Search User in System Configuration`"}} shell/shebang -.-> lab-18277{{"`Search User in System Configuration`"}} shell/comments -.-> lab-18277{{"`Search User in System Configuration`"}} shell/quoting -.-> lab-18277{{"`Search User in System Configuration`"}} shell/variables_decl -.-> lab-18277{{"`Search User in System Configuration`"}} shell/variables_usage -.-> lab-18277{{"`Search User in System Configuration`"}} shell/str_manipulation -.-> lab-18277{{"`Search User in System Configuration`"}} shell/arrays -.-> lab-18277{{"`Search User in System Configuration`"}} shell/param_expansion -.-> lab-18277{{"`Search User in System Configuration`"}} shell/for_loops -.-> lab-18277{{"`Search User in System Configuration`"}} shell/cond_expr -.-> lab-18277{{"`Search User in System Configuration`"}} shell/exit_status -.-> lab-18277{{"`Search User in System Configuration`"}} shell/func_def -.-> lab-18277{{"`Search User in System Configuration`"}} shell/arith_expansion -.-> lab-18277{{"`Search User in System Configuration`"}} shell/read_input -.-> lab-18277{{"`Search User in System Configuration`"}} shell/cmd_substitution -.-> lab-18277{{"`Search User in System Configuration`"}} shell/subshells -.-> lab-18277{{"`Search User in System Configuration`"}} shell/globbing_expansion -.-> lab-18277{{"`Search User in System Configuration`"}} end

In this challenge, you are tasked with writing a script to search for a user present in the system. You will need to fetch usernames from the first field in the /etc/passwd file and search for a given name in the list.

Tasks

You need to complete the following task:

Write a script to fetch usernames from the /etc/passwd file and search for a given name in the list.

Requirements

You must meet the following requirements:

Script name: userSearch.sh
Working directory: ~/project
Familiarity with df, cut & tr commands
Basic understanding of loops and arrays

Example

labex:project/ $ bash userSearch.sh

[INPUT] Enter the username [INPUT]
labex

[OUTPUT] USER labex IS PRESENT [OUTPUT]

labex:project/ $ bash userSearch.sh

[INPUT] Enter the username [INPUT]
123

[OUTPUT] USER 123 IS NOT PRESENT [OUTPUT]

Search User in System Configuration