用于组合3个文件的shell脚本

这应该有效:

#!/bin/bash
for FRUIT in $( cat "$@" | cut -d "," -f 1 | sort | uniq )
do
    echo -ne "${FRUIT},"
    awk -F "," "\$1 == \"$FRUIT\" {printf(\"%s|\",\$2)}" "$@" | sed 's/.$/\'$'\n/'
done

运行方式:

$ ./script.sh File1.txt File2.txt File3.txt

纯本机bash解决方案(不调用外部工具,因此仅受bash本身的性能限制)可能如下所示:

#!/usr/bin/env bash
case $BASH_VERSION in ''|[123].*) echo "ERROR: Bash 4 or newer required" >&2; exit 1;; esac

declare -A items=( )
for file in "$@"; do
  while IFS=, read -r key value; do
    items[$key]+="|$value"
  done <"$file"
done

for key in "${!items[@]}"; do
  value=${items[$key]}
  printf '%s,%s\n' "$key" "${value#'|'}"
done

…称为 ./yourscript File1.txt File2.txt File3.txt

用一个 awk 命令:

awk 'BEGIN{FS=OFS=","} {a[$1] = a[$1] (a[$1] == "" ? "" : "|") $2}
END {for (i in a) print i, a[i]}' File{1,2,3}.txt

Orange,June
Banana,Dec
Apple,May|Jan|March
Grapes,June
Mango,July|Feb

如果希望输出与原始文件中字符串的显示顺序相同,请使用以下命令 锥子 :

awk 'BEGIN{FS=OFS=","} !($1 in a) {b[++n] = $1}
{a[$1] = a[$1] (a[$1] == "" ? "" : "|") $2}
END {for (i=1; i<=n; i++) print b[i], a[b[i]]}' File{1,2,3}.txt

Apple,May|Jan|March
Orange,June
Mango,July|Feb
Grapes,June
Banana,Dec