\\\\个符号和\\\\\个符号的结果为何一致？

yufeiluo

    debian8@debian:~$ awk 'BEGIN{system("printf '%x\\\\n'  32")}'
    20ndebian8@debian:~$ awk 'BEGIN{system("printf '%x\\\\\n'  32")}'20ndebian8@debian:~$

请问，他们的输出为何都是  无换行的20n?

jason680

回复 1# yufeiluo

$ set -x
$ awk 'BEGIN{system("printf '%x\\\\n'  32")}'
+ awk 'BEGIN{system("printf %x\\n  32")}'                <== awk get this after shell
20n$ awk 'BEGIN{system("printf '%x\\\\\n'  32")}'
+ awk 'BEGIN{system("printf %x\\n  32")}'                <== they are the same result
20n$

你以为是...
$ awk 'BEGIN{system("printf '%x\\\\n'  32")}'

实际是...
$ awk 'BEGIN{system("printf '  +   %x\\\\n   +    '  32")}'


$ awk 'BEGIN{system("printf \047%x\n\047  32")}'
+ awk 'BEGIN{system("printf \047%x\n\047  32")}'
20