I'm attempting to execute diff from within a awk script thusly...
我试图在awk脚本中执行diff ...
cmd="diff <(echo \""bServers[nonServers]"\") <(echo \""primeReference"\")"
print cmd
while (( cmd | getline result) > 0 ) {print result}
close(cmd)}
...where bServers[nonServers] and primeReference evaluate as vanilla strings with no special characters. Hence the "print cmd" produces...
...其中bServers [nonServers]和primeReference评估为没有特殊字符的vanilla字符串。因此“print cmd”会产生......
diff <(echo "
> /var/tmp/text1.txt 818e9c0fc3dd92e86c80704419b1cc0d") <(echo "
> /var/tmp/text2.txt 00efcc10b376dbdd6d0972635eb650c4")
2c2
< /var/tmp/text1.txt 818e9c0fc3dd92e86c80704419b1cc0d
---
> /var/tmp/text2.txt 00efcc10b376dbdd6d0972635eb650c4
...which works fine when cut and paste to the command line. but when run as part of the Awk command returns...
...剪切并粘贴到命令行时工作正常。但是当作为Awk命令的一部分运行时返回...
/var/tmp/text2.txt 818e9c0fc3dd92e86c80704419b1cc0d")
sh: -c: line 0: syntax error near unexpected token `('
'h: -c: line 0: `diff <(echo "
A single escaping backslash before the open bracket produces...
打开支架前的单个转义反斜杠产生......
awk: warning: escape sequence `\(' treated as plain `('
Double produces...
双产......
sh: (echo: No such file or directory
Triple backslashes produces...
三个反斜杠产生......
awk: warning: escape sequence `\(' treated as plain `('
...
sh: (echo: No such file or directory
...and four backslashes (for laughs) just repeats the cycle with an ever increasing number of backslashes ad infinitum.
......和四个反斜杠（笑声）只是无限地反复循环，不断增加反斜率。
The shell is GNU bash version 4.1.2(1)-release, awk is GNU Awk 3.1.7 and OS is CentOS release 6.2 (Final).
shell是GNU bash版本4.1.2（1）-release，awk是GNU Awk 3.1.7，OS是CentOS版本6.2（最终版）。
I've tried variations with single quotes to no avail as well, does anyone have any idea where my shell-escape-foo is lacking?
我尝试使用单引号的变体也没有用，有没有人知道我的shell-escape-foo缺少哪里？
1 个解决方案
#1
1
sh is the default shell in awk and not bash so it's better if you just use bash as a whole if possible. Bash also runs in POSIX mode if ran as sh and doesn't recognize process substitution (<(..)). However you can try disabling POSIX mode if sh is actually a link to bash e.g.
sh是awk中的默认shell而不是bash所以如果可能的话，你最好只使用bash作为一个整体。如果以sh运行并且不识别进程替换（<（..）），Bash也在POSIX模式下运行。但是，如果sh实际上是bash的链接，则可以尝试禁用POSIX模式，例如
cmd="shopt +o posix\ndiff <(echo \""bServers[nonServers]"\") <(echo \""primeReference"\")"
Or explicitly call bash:
或明确调用bash：
cmd="bash -c \"exec diff <(echo '"bServers[nonServers]"') <(echo '"primeReference"')\""
The values bServers[nonServers] and primeReference could still affect syntax though. This is the reason why using bash as a whole would be preferrable most of the time when reading output of external commands is needed.
值bServers [nonServers]和primeReference仍然会影响语法。这就是为什么在需要读取外部命令输出时大多数时候使用bash作为一个整体的优选原因。
#1
1
sh is the default shell in awk and not bash so it's better if you just use bash as a whole if possible. Bash also runs in POSIX mode if ran as sh and doesn't recognize process substitution (<(..)). However you can try disabling POSIX mode if sh is actually a link to bash e.g.
sh是awk中的默认shell而不是bash所以如果可能的话，你最好只使用bash作为一个整体。如果以sh运行并且不识别进程替换（<（..）），Bash也在POSIX模式下运行。但是，如果sh实际上是bash的链接，则可以尝试禁用POSIX模式，例如
cmd="shopt +o posix\ndiff <(echo \""bServers[nonServers]"\") <(echo \""primeReference"\")"
Or explicitly call bash:
或明确调用bash：
cmd="bash -c \"exec diff <(echo '"bServers[nonServers]"') <(echo '"primeReference"')\""
The values bServers[nonServers] and primeReference could still affect syntax though. This is the reason why using bash as a whole would be preferrable most of the time when reading output of external commands is needed.
值bServers [nonServers]和primeReference仍然会影响语法。这就是为什么在需要读取外部命令输出时大多数时候使用bash作为一个整体的优选原因。