> ## Documentation Index > Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt > Use this file to discover all available pages before exploring further. # Find > Learn to use `sed` for searching, printing, and deleting text patterns in files efficiently. Enhance your text-processing workflow by using `sed` to search, print, or delete specific patterns directly within files. While similar to [grep](https://www.gnu.org/software/grep/manual/grep.html), `sed` lets you combine pattern matching with editing commands in one step. To follow along, we’ll use an `employees.txt` file with records formatted as `ID|First|Last|Department|Role|Email|Salary`. ![The image shows a text file named "employees.txt" containing a list of employees with details such as name, department, job title, email, and salary.](https://kodekloud.com/kk-media/image/upload/v1752868669/notes-assets/images/Advanced-Bash-Scripting-Find/employees-list-details-text-file.jpg) ## 1. Basic Search Syntax `sed` requires both a pattern and an action. The minimal form is: ```bash theme={null} sed '/pattern/' file ``` Without an explicit action, `sed` may default to printing every line or throw an error: ```bash theme={null} $ sed '/Manager/' employees.txt # (No command given; behavior depends on your sed version) ``` To print only matching lines, use `-n` (quiet mode) with the `p` command: ```bash theme={null} sed -n '/Manager/p' employees.txt ``` * `-n` : suppress automatic printing * `/Manager/` : search for “Manager” * `p` : print matching lines ```bash theme={null} $ sed -n '/Manager/p' employees.txt 5|Feng|Lin|Sales|Sales Manager|feng.lin@company.com|90000 6|Andy|Luscomb|IT|IT Manager|andy.luscomb@company.com|95000 7|Mark|Crocker|HR|HR Manager|mark.crocker@company.com|85000 8|Jing|Ma|Engineering|Engineering Manager|jing.ma@company.com|100000 ``` By default, `sed` performs case-sensitive matches. Searching for `manager` (lowercase) yields no results: ```bash theme={null} $ sed -n '/manager/p' employees.txt # No match ``` ## 2. Searching Substrings Match partial strings by specifying only a fragment: ```bash theme={null} $ sed -n '/Ma/p' employees.txt 4|Enrique|Rivera|Marketing|Marketing Specialist|enrique.rivera@company.com|65000 5|Feng|Lin|Sales|Sales Manager|feng.lin@company.com|90000 6|Andy|Luscomb|IT|IT Manager|andy.luscomb@company.com|95000 7|Mark|Crocker|HR|HR Manager|mark.crocker@company.com|85000 8|Jing|Ma|Engineering|Engineering Manager|jing.ma@company.com|100000 ``` This matches “Marketing”, “Manager”, “Mark”, and the last name “Ma”. ## 3. Exact Word Matches with Word Boundaries Use `\<` and `\>` to match whole words only: ```bash theme={null} sed -n '/\/p' employees.txt ``` ```bash theme={null} $ sed -n '/\/p' employees.txt 8|Jing|Ma|Engineering|Engineering Manager|jing.ma@company.com|100000 ``` **Command breakdown:** * `sed` : invoke stream editor * `-n` : suppress default output * `/\/` : match exact word “Ma” * `p` : print matching line ## 4. Combining Multiple Search Patterns Chain multiple scripts with `-e` to search for more than one pattern: ```bash theme={null} sed -n \ -e '/\/p' \ -e '/\/p' \ employees.txt ``` ```bash theme={null} $ sed -n -e '/\/p' -e '/\/p' employees.txt 3|Debbie|Miller|IT|Software Developer|debbie.miller@company.com|80000 5|Feng|Lin|Sales|Sales Manager|feng.lin@company.com|90000 6|Andy|Luscomb|IT|IT Manager|andy.luscomb@company.com|95000 7|Mark|Crocker|HR|HR Manager|mark.crocker@company.com|85000 8|Jing|Ma|Engineering|Engineering Manager|jing.ma@company.com|100000 ``` Lines matching either pattern appear once per script. ## 5. Deleting Matches Swap `p` for `d` to remove matching lines: Remove Enrique’s record: ```bash theme={null} sed -e '/\/d' employees.txt ``` Delete all lines containing “Ma” as a whole word: ```bash theme={null} $ sed -e '/\/d' employees.txt 1|Kriti|Shreshtha|Finance|Financial Analyst|kriti.shreshtha@company.com|60000 2|Rajasekar|Vasudevan|Finance|Senior Accountant|rajasekar.vasudevan@company.com|75000 3|Debbie|Miller|IT|Software Developer|debbie.miller@company.com|80000 4|Enrique|Rivera|Marketing|Marketing Specialist|enrique.rivera@company.com|65000 5|Feng|Lin|Sales|Sales Manager|feng.lin@company.com|90000 6|Andy|Luscomb|IT|IT Manager|andy.luscomb@company.com|95000 7|Mark|Crocker|HR|HR Manager|mark.crocker@company.com|85000 ``` ## 6. Editing Files In-Place with `-i` Apply deletions or substitutions directly using `-i`: ```bash theme={null} $ sed -i \ -e '/\/d' \ -e '/\/d' \ employees.txt $ cat employees.txt 1|Kriti|Shreshtha|Finance|Financial Analyst|kriti.shreshtha@company.com|60000 2|Rajasekar|Vasudevan|Finance|Senior Accountant|rajasekar.vasudevan@company.com|75000 4|Enrique|Rivera|Marketing|Marketing Specialist|enrique.rivera@company.com|65000 ``` Using `-i` overwrites your source file. Always keep backups or use version control. ## 7. Quick Reference: sed Flags | Option | Description | Example | | ------ | --------------------------- | ------------------------------ | | -n | Suppress automatic printing | `sed -n '/pattern/p' file` | | -i | Edit files in-place | `sed -i 's/foo/bar/' file` | | -e | Add multiple scripts | `sed -e '/A/p' -e '/B/p' file` | *** ![The image is a checklist titled "sed search," highlighting topics such as using the search function with print and delete commands, expressing the dash e flag for multiple scripts, and revisiting the use of flags -n and -i.](https://kodekloud.com/kk-media/image/upload/v1752868669/notes-assets/images/Advanced-Bash-Scripting-Find/sed-search-checklist-flags.jpg) ## Links and References * [GNU sed Manual](https://www.gnu.org/software/sed/manual/sed.html) * [Regular Expressions Basics](https://www.regular-expressions.info/) * [grep vs sed Comparison](https://www.baeldung.com/linux/grep-sed)