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CLI: File & Text

CLI: File & Text #

Benchmark for some of the examples:

curl --head --silent google.com
# HTTP/1.1 301 Moved Permanently
# Location: http://www.google.com/
# Content-Type: text/html; charset=UTF-8
# Date: Fri, 07 Aug 2020 18:26:00 GMT
# Expires: Sun, 06 Sep 2020 18:26:00 GMT
# Cache-Control: public, max-age=2592000
# Server: gws
# Content-Length: 219
# X-XSS-Protection: 0
# X-Frame-Options: SAMEORIGIN
#

fzf (find files) #

Repository: junegunn/fzf: A command-line fuzzy finder
A great demo video: Vim universe. fzf - command line fuzzy finder - YouTube

[Question] how can I toggle exact match behavior in fzf · Issue #1265 · junegunn/fzf

grep #

Online manual: grep(1) - Linux manual page

  • Use extended regex: grep -E or egrep (E for extended-regexp)
  • Use fixed string instead of regex: grep -F or fgrep (F for fixed-strings)
  • Reverse match (match without): grep -v (v for invert-match)

Example:

curl --head --silent google.com | grep GMT
# Date: Fri, 07 Aug 2020 19:19:53 GMT
# Expires: Sun, 06 Sep 2020 19:19:53 GMT

ripgrep, rg #

Repository: BurntSushi/ripgrep: ripgrep recursively searches directories for a regex pattern
Guide: ripgrep/GUIDE.md at master · BurntSushi/ripgrep

  • Literal match: rg -F <string> (F for fixed-strings)
  • Case insensitive: rg -i (i for ignore-case)

Example: find text in all files in current directory

rg -i readme
# programming/static-site/gatsby.md
# 73:    ├── README.md
# 
# computer/software-usage/command-line-built-in.md
# 139:$ cat README.md
# 148:$ tac README.md
# 
# computer/software-usage/command-line-others.md
# 55:$ rg -i readme
# 57:# 139:$ cat README.md
# 58:# 148:$ tac README.md
# 61:# 3:* [Introduction](README.md)
# 62:# 32:* [Python](programming/python/README.md)
# 63:# 56:* [衣着打扮](life-log/dressing-grooming/README.md)
# 64:# 65:* [Entertainment](life-log/entertainment/README.md)
# 67:# 73:    ├── README.md
# 
# SUMMARY.md
# 3:* [Introduction](README.md)
# 32:* [Python](programming/python/README.md)
# 56:* [衣着打扮](life-log/dressing-grooming/README.md)
# 65:* [Entertainment](life-log/entertainment/README.md)

head, tail #

Online manual:

Example:

curl --head --silent google.com | head -n 2
# HTTP/1.1 301 Moved Permanently
# Location: http://www.google.com/

curl --head --silent google.com | tail -n 2
# X-Frame-Options: SAMEORIGIN
#

less (man, git diff, git log, etc.) #

Online manual: less(1) - Linux manual page

Text displayer, aka, pager.

curl www.google.com | less

bat (cat, less) #

Repository: sharkdp/bat: A cat(1) clone with wings.

  • Show non-printable characters: bat -A (A for show-all)

Change theme: (in ~/.zshrc)

export BAT_THEME='ansi-dark'

Example:

# Compare the outcomes:

curl www.google.com | less
curl www.google.com | bat

sed #

Online manual: sed(1) - Linux manual page
Documentation: sed, a stream editor

  • Non-greedy regex matching: sed -E 's/regex/replacement/' (E for regexp-extended)
  • Greedy matching: sed -E 's/regex/replacement/g'

Example 1:

curl --head --silent google.com | grep GMT | sed -E 's/^.*[A-Za-z]{3}, [0-9]{2} [A-Za-z]{3} 2020 (.*)$/\1/'
# 19:40:05 GMT
# 19:40:05 GMT

Example 2: FizzBuzz (credit)

seq 15 | sed '/.*[05]$/s//Buzz/; n; s//Buzz/; n; s//Buzz/; s/^[0-9]*/Fizz/'
# 1
# 2
# Fizz
# 4
# Buzz
# Fizz
# 7
# 8
# Fizz
# Buzz
# 11
# Fizz
# 13
# 14
# FizzBuzz

sort #

Online manual: sort(1) - Linux manual page

  • Ascending order: (A-Z): sort
  • Descending order (Z-A): sort -r (r for reverse)
  • Ascending number order (1-9): sort -n (n for numeric-sort)
  • Descending number order (9-1): sort -nr

split #

Refs:

tac #

Online manual: tac(1) - Linux manual page

Display output upside-down, i.e., the reverse of cat.

Example 1:

cat README.md
# # Introduction
# 
# My personal wiki, cheat sheet, knowledge base…
# Each page is written in the language in which I think about the topic.
# 
# An experiment inspired by [Nikita Voloboev's Personal Wiki](https://wiki.nikitavoloboev.xyz/).
# 

tac README.md
# 
# An experiment inspired by [Nikita Voloboev's Personal Wiki](https://wiki.nikitavoloboev.xyz/).
# 
# Each page is written in the language in which I think about the topic.
# My personal wiki, cheat sheet, knowledge base…
# 
# # Introduction

Example 2:

curl --head --silent google.com | tac
# 
# X-Frame-Options: SAMEORIGIN
# X-XSS-Protection: 0
# Content-Length: 219
# Server: gws
# Cache-Control: public, max-age=2592000
# Expires: Sun, 06 Sep 2020 18:26:04 GMT
# Date: Fri, 07 Aug 2020 18:26:04 GMT
# Content-Type: text/html; charset=UTF-8
# Location: http://www.google.com/
# HTTP/1.1 301 Moved Permanently

tee #

Online manual: tee(1) - Linux manual page

Ref: shell - How can I send stdout to multiple commands? - Unix & Linux Stack Exchange

Pass output to other command(s), and then echo output.

echo '<a href="https://unix.stackexchange.com/a/28519" rel="nofollow noopener noreferrer">shell - How can I send stdout to multiple commands? - Unix & Linux Stack Exchange</a>' | textutil -stdin -format html -convert rtf -stdout | tee >(pbcopy -pboard general -Prefer public.rtf)

# {\rtf1\ansi\ansicpg936\cocoartf2513
# \cocoatextscaling0\cocoaplatform0{\fonttbl\f0\froman\fcharset0 Times-Roman;}
# {\colortbl;\red255\green255\blue255;\red0\green0\blue233;\red0\green0\blue0;}
# {\*\expandedcolortbl;;\cssrgb\c0\c0\c93333;\cssrgb\c0\c0\c0;}
# \deftab720
# \pard\pardeftab720\partightenfactor0
# {\field{\*\fldinst{HYPERLINK "https://unix.stackexchange.com/a/28519"}}{\fldrslt 
# \f0\fs24 \cf2 \expnd0\expndtw0\kerning0
# \ul \ulc2 \outl0\strokewidth0 \strokec2 shell - How can I send stdout to multiple commands? - Unix & Linux Stack Exchange}}
# \f0\fs24 \cf3 \expnd0\expndtw0\kerning0
# \outl0\strokewidth0 \strokec3  }

uniq #

Online manual: uniq(1) - Linux manual page

  • Display number of occurrences of each line, sorted by the most frequent: sort <file> | uniq -c | sort -nr (c for count, n for number, r for reverse)

wc #

Online manual: wc(1) - Linux manual page

Count number of lines/words/characters.

Example:

curl --head --silent google.com | wc --lines
curl --head --silent google.com | wc -l
#       11

macOS specific commands #

textutil #

Online manual: textutil Man Page - macOS - SS64.com

pbcopy #

Online manual: pbcopy Man Page - macOS - SS64.com

Calendar September 15, 2023