linux批量替换小写字母

sed 's/a/b/g' input.txt > output.txt

for file in *.txt; do
    sed 's/a/b/g' "$file" > "${file%.txt}_modified.txt"
done

tr 'a-z' 'A-Z' < input.txt > output.txt

#!/bin/bash

for file in *.txt; do
    while IFS= read -r line; do
        new_line=""
        for (( i=0; i<${#line}; i++ )); do
            char="${line:$i:1}"
            if [[ "$char" =~ [a-z] ]]; then
                # 将小写字母转换为下一个字母，z循环到a
                if [ "$char" == "z" ]; then
                    new_char="a"
                else
                    new_char=$(echo "$char" | tr 'a-z' 'b-za')
                fi
                new_line+="$new_char"
            else
                new_line+="$char"
            fi
        done
        echo "$new_line"
    done < "$file" > "${file%.txt}_modified.txt"
done

#!/usr/bin/perl
use strict;
use warnings;

foreach my $file (@ARGV) {
    open(my $in, '<', $file) or die "无法打开 $file: $!";
    open(my $out, '>', "${file}_modified") or die "无法创建 ${file}_modified: $!";
    while (my $line = <$in>) {
        $line =~ s/a/b/g;
        print $out $line;
    }
    close($in);
    close($out);
}