info [選項(xiàng)] [主題] [節(jié)點(diǎn)]

sudo apt install texinfo  # Ubuntu
sudo dnf install texinfo  # CentOS

info --version

info (GNU texinfo) 7.1

dpkg -l | grep texinfo  # Ubuntu
rpm -q texinfo         # CentOS

ls /usr/share/info | head -n 5

bash.info.gz
coreutils.info.gz
gcc.info.gz
glibc.info.gz
make.info.gz

info bash

File: bash.info,  Node: Top,  Next: Introduction,  Up: (dir)

Bash Reference Manual
********************

This manual is the reference for Bash, the GNU Bourne-Again Shell...

* Menu:
* Introduction::       An introduction to the shell.
* Definitions::        Some definitions used in the rest of this manual.
* Basic Shell Features::  The basic features of the shell.
...
--:--  (bash)Top

info bash 'Shell Variables'

File: bash.info,  Node: Shell Variables,  Next: Bash Variables,  Up: Variables

5.2 Shell Variables
==================

Variables are used to store data in the shell...

* Menu:
* Bourne Shell Variables:: Variables recognized by Bourne shells.
* Special Parameters::    Parameters with special meaning.
...

info bash 'Shell Variables' -o /tmp/variables.txt
cat /tmp/variables.txt | head -n 10

Shell Variables
***************

Variables are used to store data in the shell...

   * Bourne Shell Variables: Variables recognized by Bourne shells.
   * Special Parameters: Parameters with special meaning.
...

info --apropos grep

"(coreutils)grep invocation" -- grep
"(grep)Top" -- grep
"(regex)Top" -- Regular Expressions
...

info bash --index-search PATH

File: bash.info,  Node: Bourne Shell Variables,  Up: Shell Variables

5.2.1 Bourne Shell Variables
----------------------------

`PATH`
     The search path for commands...

info --where bash

/usr/share/info/bash.info.gz

info -f /usr/share/info/gcc.info.gz

info bash --subnodes -o /tmp/bash_full.txt

export INFOPATH=/custom/info:$INFOPATH
info mydoc

#!/bin/bash
TOPICS=("bash" "gcc" "make")
for topic in "${TOPICS[@]}"; do
    info "$topic" --subnodes -o "/tmp/${topic}_doc.txt"
    echo "已提取 $topic 文檔"
done

已提取 bash 文檔
已提取 gcc 文檔
已提取 make 文檔

\input texinfo
@setfilename example.info
@settitle 示例手冊(cè)

@node Top
@top 示例手冊(cè)

這是一個(gè)示例 Info 文檔。

@menu
* 第一章:: 第一章內(nèi)容。
@end menu

@node 第一章
@chapter 第一章

第一章的內(nèi)容。
@end texinfo

makeinfo --info /tmp/example.texi -o /tmp/example.info
info -f /tmp/example.info

File: example.info,  Node: Top,  Next: 第一章,  Up: (dir)

示例手冊(cè)
********

這是一個(gè)示例 Info 文檔。

* Menu:
* 第一章:: 第一章內(nèi)容。

info bash --subnodes | grep -i "environment variable"

5.2 Shell Variables
     Environment variables are used to...
   * PATH: The search path for commands.
...

#!/bin/bash
TOPIC=$1
KEYWORD=$2
info "$TOPIC" --index-search="$KEYWORD" -o /tmp/result.txt
if [ $? -eq 0 ]; then
    cat /tmp/result.txt | head -n 10
else
    echo "在 $TOPIC 中未找到 $KEYWORD"
fi

./script.sh bash PATH

`PATH`
     The search path for commands...

mkdir /tmp/custom_info
cp /tmp/example.info /tmp/custom_info/
export INFOPATH=/tmp/custom_info:$INFOPATH
info example

File: example.info,  Node: Top,  Next: 第一章,  Up: (dir)
...

sudo apt install bash-doc  # Ubuntu

man bash

echo $INFOPATH

#!/bin/bash
echo "輸入主題（如 bash、gcc）："
read topic
info "$topic" --subnodes -o "/tmp/${topic}_ref.txt"
gzip "/tmp/${topic}_ref.txt"
echo "文檔已保存為 /tmp/${topic}_ref.txt.gz"

輸入主題（如 bash、gcc）：
bash
文檔已保存為 /tmp/bash_ref.txt.gz

#!/bin/bash
TOPIC="coreutils"
KEYWORDS=("ls" "cp" "mv")
for keyword in "${KEYWORDS[@]}"; do
    echo "在 $TOPIC 中搜索 $keyword："
    info "$TOPIC" --index-search="$keyword" -o "/tmp/${keyword}.txt"
    cat "/tmp/${keyword}.txt" | head -n 5
done

在 coreutils 中搜索 ls：
`ls`
     List directory contents...
在 coreutils 中搜索 cp：
`cp`
     Copy files and directories...

#!/bin/bash
INFO_FILE=/tmp/example.info
if [ -O "$INFO_FILE" ]; then
    info -f "$INFO_FILE"
else
    echo "不可信的 Info 文件"
    exit 1
fi

不可信的 Info 文件

#!/bin/bash
DEST=/tmp/info_backup
mkdir -p "$DEST"
cp /usr/share/info/*.info.gz "$DEST"
for file in "$DEST"/*.info.gz; do
    info -f "$file" --subnodes -o "${file%.gz}.txt"
done
echo "備份完成，位于 $DEST"

備份完成，位于 /tmp/info_backup

#!/bin/bash
echo "輸入主題和關(guān)鍵詞（如 bash PATH）："
read topic keyword
info "$topic" --index-search="$keyword" --output=- | less

`PATH`
     The search path for commands...
（按 q 退出）