bash 解决 $1: 歧义重定向
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solve $1: ambiguous redirect
提问by John Smith
I'm using this script to backup an old private instance of postgresql to gmail periodically:
我正在使用此脚本定期将 postgresql 的旧私有实例备份到 gmail：
#!/bin/bash
/opt/local/lib/postgresql83/bin/pg_dump maxgests -U postgres | gzip --best -c > && (/opt/local/bin/mutt -s `date "+%d-%m-%Y-%H:%M"` -a < /dev/null)
As of late I'm getting this:
最近我得到了这个：
./postgres_to_gmail.sh: line 2: : ambiguous redirect
And the script no longer works. Mac OS X 10.6.8.
并且脚本不再有效。Mac OS X 10.6.8。
Can anytone tell what's wrong and how to fix it?
谁能告诉我出了什么问题以及如何解决？
First argument is a path, like /tmp/database.gz
第一个参数是一条路径，比如 /tmp/database.gz
Second argument is the email.
第二个参数是电子邮件。
回答by tripleee
$1is apparently empty.
$1显然是空的。
As a general guidance, you should put your variable interpolations in double quotes, nearly always.
作为一般指导，您应该将变量插值放在双引号中，几乎总是如此。
回答by Zoltán Haindrich
the caller doesn't set the arguments ($1 $2) you should check the crontab or the program which calls is periodically more
调用者没有设置参数 ($1 $2) 你应该检查 crontab 或定期调用的程序
$ echo >
bash: : ambiguous redirect
