文件读写 #

#!/bin/bash

# 读取整个文件
content=$(cat file.txt)

# 逐行读取
while IFS= read -r line; do
    echo "$line"
done < file.txt

# 读取到数组
mapfile -t lines < file.txt

# 读取前N行
head -n 10 file.txt

# 读取后N行
tail -n 10 file.txt

#!/bin/bash

# 覆盖写入
echo "内容" > file.txt

# 追加写入
echo "内容" >> file.txt

# 写入多行
cat > file.txt << EOF
第一行
第二行
EOF

# 使用tee
echo "内容" | tee file.txt

#!/bin/bash

read_file() {
    local file="$1"
    [[ -f "$file" ]] && cat "$file"
}

write_file() {
    local file="$1"
    local content="$2"
    echo "$content" > "$file"
}

append_file() {
    local file="$1"
    local content="$2"
    echo "$content" >> "$file"
}