如何通过shebang(即#！)使用awk的多个参数? [英] How to use multiple arguments for awk with a shebang (i.e. #!)?

问题描述

我想使用 --re 执行 gawk 脚本-interval 使用shebang.

I'd like to execute an gawk script with --re-interval using a shebang. The "naive" approach of

#!/usr/bin/gawk --re-interval -f
... awk script goes here

不起作用，因为 gawk 是用第一个参数 "--re-interval -f" 调用的(没有围绕空格分割)，它不理解.有解决方法吗?

does not work, since gawk is called with the first argument "--re-interval -f" (not splitted around the whitespace), which it does not understand. Is there a workaround for that?

当然，您可以不直接调用 gawk 而是将其包装到拆分第一个参数的 shell 脚本中，或者创建一个 shell 脚本然后调用 gawk 并将脚本放入另一个文件中，但我想知道是否有一些在一个文件中执行此操作的方法.

Of course you can either not call gawk directly but wrap it into a shell script that splits the first argument, or make a shell script that then calls gawk and put the script into another file, but I was wondering if there was some way to do this within one file.

shebang 行的行为因系统而异 - 至少在 Cygwin 中没有用空格分割参数.我只关心如何在表现如此的系统上做到这一点；该脚本并不意味着可移植.

The behaviour of shebang lines differs from system to system - at least in Cygwin it does not split the arguments by whitespaces. I just care about how to do it on a system that behaves like that; the script is not meant to be portable.

推荐答案

这对我来说似乎适用于 (g)awk.

This seems to work for me with (g)awk.

#!/bin/sh
arbitrary_long_name==0 "exec" "/usr/bin/gawk" "--re-interval" "-f" "$0" "$@"


# The real awk program starts here
{ print $0 }

注意#!运行/bin/sh，所以这个脚本首先被解释为一个shell脚本.

Note the #! runs /bin/sh, so this script is first interpreted as a shell script.

起初，我只是尝试了 "exec" "/usr/bin/gawk" "--re-interval" "-f" "$0" "$@"，但是 awk 处理了那个作为命令并无条件地打印出每一行输入.这就是为什么我输入 arbitrary_long_name==0 - 它应该一直失败.你可以用一些乱七八糟的字符串替换它.基本上，我正在 awk 中寻找一个不会对 shell 脚本产生不利影响的错误条件.

At first, I simply tried "exec" "/usr/bin/gawk" "--re-interval" "-f" "$0" "$@", but awk treated that as a command and printed out every line of input unconditionally. That is why I put in the arbitrary_long_name==0 - it's supposed to fail all the time. You could replace it with some gibberish string. Basically, I was looking for a false-condition in awk that would not adversely affect the shell script.

在 shell 脚本中，arbitrary_long_name==0 定义了一个名为 arbitrary_long_name 的变量，并将其设置为等于 =0.

In the shell script, the arbitrary_long_name==0 defines a variable called arbitrary_long_name and sets it equal to =0.

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