mark提出的问题 -unix

mark

Asked: 2023-07-29 01:38:31 +0800 CST

如何在一种特定情况下在末尾回显空格而不使用多余的引号？[复制]

6

考虑以下 bash 脚本：

~$ x="echo -n abc "

~$ $x && echo xyz
abcxyz

~$

出于好奇（请纵容我），我想要一个包含echo -n输出某些内容的命令的 bash 变量。我想知道是否可以以保留尾随空格的方式定义它。

一个明显的选择是使用引号：

~$ x="echo -n \"abc \""

~$ $x && echo xyz
"abc "xyz

~$

但这些引号会污染输出。

当然，我可以在第二个 echo 命令前面添加空格：

~$ x="echo -n abc "

~$ $x && echo " xyz"
abc xyz

~$

但问题的目的是了解是否可以用尾随空格表示输出中没有多余引号的x方式进行更改。$xecho -n

非常感谢。

mark

Asked: 2023-05-10 00:08:36 +0800 CST

我们可以将“bash: local: can only be used in a function”错误降级为警告吗？

5

现在local在顶层 shell 上使用失败：

/tmp/tmp.TvdqDYLG9T$ local x=1
bash: local: can only be used in a function

/tmp/tmp.TvdqDYLG9T$ echo $x


/tmp/tmp.TvdqDYLG9T$

我希望它工作的理由是我想通过将代码片段复制/粘贴到 shell 控制台并在那里尝试来测试我的 bash 函数。但我不能，因为local. 我必须先粘贴到记事本，删除local然后粘贴到控制台。

有没有更好的办法？

mark

Asked: 2023-05-05 21:37:47 +0800 CST

当所有证书都应该存在时，为什么从容器运行的 curl 会抱怨本地颁发者证书？

7

这是我的 docker 命令行：

mark@L-R910LPKW:~$ docker run -v /etc/ssl:/etc/ssl -v /usr/local/share/ca-certificates:/usr/local/share/ca-certificates -v /usr/share/ca-certificates:/usr/share/ca-certificates curlimages/curl -ksvo /dev/null https://registry.yarnpkg.com/csstype/-/csstype-3.0.8.tgz
*   Trying 104.16.19.35:443...
* Connected to registry.yarnpkg.com (104.16.19.35) port 443 (#0)
* ALPN: offers h2,http/1.1
} [5 bytes data]
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
} [512 bytes data]
* TLSv1.3 (IN), TLS handshake, Server hello (2):
{ [88 bytes data]
* TLSv1.3 (OUT), TLS change cipher, Change cipher spec (1):
} [1 bytes data]
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
} [512 bytes data]
* TLSv1.3 (IN), TLS handshake, Server hello (2):
{ [155 bytes data]
* TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8):
{ [6 bytes data]
* TLSv1.3 (IN), TLS handshake, Certificate (11):
{ [3297 bytes data]
* TLSv1.3 (IN), TLS handshake, CERT verify (15):
{ [264 bytes data]
* TLSv1.3 (IN), TLS handshake, Finished (20):
{ [52 bytes data]
* TLSv1.3 (OUT), TLS handshake, Finished (20):
} [52 bytes data]
* SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384
* ALPN: server did not agree on a protocol. Uses default.
* Server certificate:
*  subject: C=US; ST=California; L=San Francisco; O=Cloudflare, Inc.; CN=registry.yarnpkg.com
*  start date: Apr 29 02:29:46 2023 GMT
*  expire date: May 13 02:29:46 2023 GMT
*  issuer: C=US; ST=California; O=Zscaler Inc.; OU=Zscaler Inc.; CN=Zscaler Intermediate Root CA (zscalertwo.net) (t)
*  SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.
* using HTTP/1.x
} [5 bytes data]
> GET /csstype/-/csstype-3.0.8.tgz HTTP/1.1
> Host: registry.yarnpkg.com
> User-Agent: curl/8.0.1-DEV
> Accept: */*
>
{ [5 bytes data]
< HTTP/1.1 200 OK
< Date: Fri, 05 May 2023 02:17:14 GMT
< Content-Type: application/octet-stream
< Content-Length: 175305
< Connection: keep-alive
< CF-Ray: 7c257c694f4253f5-YYZ
< Accept-Ranges: bytes
< Access-Control-Allow-Origin: *
< Age: 1689328
< Cache-Control: public, immutable, max-age=31557600
< ETag: "a06dac7944c631c06fa7509c9095ca08"
< Last-Modified: Mon, 19 Apr 2021 07:35:13 GMT
< Vary: Accept-Encoding
< CF-Cache-Status: HIT
< Server: cloudflare
<
{ [14612 bytes data]
* Connection #0 to host registry.yarnpkg.com left intact
mark@L-R910LPKW:~$

这是一个公司网络，所以我们让 Zscaler 充当 MITM。

我不明白为什么 curl “无法获得本地颁发者证书”。我可以在主机上运行相同的命令行就好了：

mark@L-R910LPKW:~$ curl -svo /dev/null https://registry.yarnpkg.com/csstype/-/csstype-3.0.8.tgz
*   Trying 104.16.19.35:443...
* Connected to registry.yarnpkg.com (104.16.19.35) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
*  CAfile: /etc/ssl/certs/ca-certificates.crt
*  CApath: /etc/ssl/certs
* TLSv1.0 (OUT), TLS header, Certificate Status (22):
} [5 bytes data]
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
} [512 bytes data]
* TLSv1.2 (IN), TLS header, Certificate Status (22):
{ [5 bytes data]
* TLSv1.3 (IN), TLS handshake, Server hello (2):
{ [88 bytes data]
* TLSv1.2 (OUT), TLS header, Finished (20):
} [5 bytes data]
* TLSv1.3 (OUT), TLS change cipher, Change cipher spec (1):
} [1 bytes data]
* TLSv1.2 (OUT), TLS header, Certificate Status (22):
} [5 bytes data]
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
} [512 bytes data]
* TLSv1.2 (IN), TLS header, Finished (20):
{ [5 bytes data]
* TLSv1.2 (IN), TLS header, Certificate Status (22):
{ [5 bytes data]
* TLSv1.3 (IN), TLS handshake, Server hello (2):
{ [155 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8):
{ [6 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.3 (IN), TLS handshake, Certificate (11):
{ [3297 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.3 (IN), TLS handshake, CERT verify (15):
{ [264 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.3 (IN), TLS handshake, Finished (20):
{ [52 bytes data]
* TLSv1.2 (OUT), TLS header, Supplemental data (23):
} [5 bytes data]
* TLSv1.3 (OUT), TLS handshake, Finished (20):
} [52 bytes data]
* SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384
* ALPN, server did not agree to a protocol
* Server certificate:
*  subject: C=US; ST=California; L=San Francisco; O=Cloudflare, Inc.; CN=registry.yarnpkg.com
*  start date: Apr 29 02:29:46 2023 GMT
*  expire date: May 13 02:29:46 2023 GMT
*  subjectAltName: host "registry.yarnpkg.com" matched cert's "registry.yarnpkg.com"
*  issuer: C=US; ST=California; O=Zscaler Inc.; OU=Zscaler Inc.; CN=Zscaler Intermediate Root CA (zscalertwo.net) (t)
*  SSL certificate verify ok.
* TLSv1.2 (OUT), TLS header, Supplemental data (23):
} [5 bytes data]
> GET /csstype/-/csstype-3.0.8.tgz HTTP/1.1
> Host: registry.yarnpkg.com
> User-Agent: curl/7.81.0
> Accept: */*
>
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< Date: Fri, 05 May 2023 02:25:46 GMT
< Content-Type: application/octet-stream
< Content-Length: 175305
< Connection: keep-alive
< CF-Ray: 7c2588e75bada216-YYZ
< Accept-Ranges: bytes
< Access-Control-Allow-Origin: *
< Age: 1689840
< Cache-Control: public, immutable, max-age=31557600
< ETag: "a06dac7944c631c06fa7509c9095ca08"
< Last-Modified: Mon, 19 Apr 2021 07:35:13 GMT
< Vary: Accept-Encoding
< CF-Cache-Status: HIT
< Server: cloudflare
<
{ [14612 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* TLSv1.2 (IN), TLS header, Supplemental data (23):
{ [5 bytes data]
* Connection #0 to host registry.yarnpkg.com left intact
mark@L-R910LPKW:~$

为什么我认为容器中的卷曲应该可以正常工作？因为我将所有相同的证书目录从主机挂载到容器中：

/etc/ssl
/usr/local/share/ca-证书
/usr/share/ca-证书

所以大概容器“看到”与主机相同的证书。那么为什么它不起作用？

编辑 1

这是一个注入了 Zscaler 证书的企业网络。如果您不在类似的环境中，您将无法干净地重现它。我的问题是概念性的——我似乎通过各种挂载在容器中复制了我的主机环境，但是当主机通过时容器失败了。

编辑 2

为了进行实验，我切换到了以下 Dockerfile：

FROM nginxinc/nginx-unprivileged:1.23.3-alpine-slim
USER 0
ARG chip_user_pwd
RUN apk update && \
    apk add --no-cache sudo curl busybox-extras bind-tools nmap-ncat openssl netcat-openbsd openssh git strace && \
    adduser -u 1000 -D chip && \
    echo "chip:$chip_user_pwd" | chpasswd && \
    echo "chip ALL=(ALL) ALL" > /etc/sudoers.d/chip && \
    chgrp -R chip /etc/nginx/conf.d && \
    chmod 0440 /etc/sudoers.d/chip
COPY default.conf.template /etc/nginx/templates/default.conf.template
USER 101

（我用它来解决问题）

运行容器的命令行是：

docker run --cap-add=SYS_PTRACE -d -v /etc/ssl:/etc/ssl -v /usr/local/share/ca-certificates:/usr/local/share/ca-certificates -v /usr/share/ca-certificates:/usr/share/ca-certificates OurACR.azurecr.io/chip/toolbox sleep 1d

它显示与卷曲图像相同的行为。我在容器和主机上运行strace（感谢https://jvns.ca/blog/2020/04/29/why-strace-doesnt-work-in-docker/的说明）。

两者都从/etc/ssl/certs/ca-certificates.crt读取：

然而，一旦读完，他们就会做不同的事情：

最后，在主机上运行的进程开始读取 ZScaler 证书之一，而在容器上运行的进程我不知道是什么：

在哪里：

mark@L-R910LPKW:~$ ls -l /etc/ssl/certs/f36a1d00.0
lrwxrwxrwx 1 root root 54 Apr 21 16:46 /etc/ssl/certs/f36a1d00.0 -> 'Zscaler_Intermediate_Root_CA_=zscalertwo.net=_=t=_.pem'
mark@L-R910LPKW:~$

因为它是 strace 包含很多噪音。很想知道如何以有意义的方式减少它。

忘了说了。主机/lib/x86_64-linux-gnu/libssl.so.3在 docker 容器加载时加载/lib/libssl.so.3。也许这很重要。

编辑 3

使用的原始建议建议strace用来调用它-e trace=%file，我们开始吧：

码头工人

/ # strace -e trace=%file -f curl -so /dev/null https://dl-cdn.alpinelinux.org/alpine/v3.17/main
execve("/usr/bin/curl", ["curl", "-so", "/dev/null", "https://dl-cdn.alpinelinux.org/a"...], 0x7fff23ab9330 /* 8 vars */) = 0
open("/etc/ld-musl-x86_64.path", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/lib/libcurl.so.4", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/local/lib/libcurl.so.4", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib/libcurl.so.4", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
open("/lib/libz.so.1", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
open("/lib/libnghttp2.so.14", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/local/lib/libnghttp2.so.14", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib/libnghttp2.so.14", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
open("/lib/libssl.so.3", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
open("/lib/libcrypto.so.3", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
open("/lib/libbrotlidec.so.1", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/local/lib/libbrotlidec.so.1", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib/libbrotlidec.so.1", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
open("/lib/libbrotlicommon.so.1", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/local/lib/libbrotlicommon.so.1", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib/libbrotlicommon.so.1", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
open("/etc/ssl/openssl.cnf", O_RDONLY|O_LARGEFILE) = 3
open("/root/.curlrc", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/root/.config/curlrc", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/etc/passwd", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
open("/root/.curlrc", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
strace: Process 37 attached
[pid    37] open("/etc/hosts", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 7
[pid    37] open("/etc/resolv.conf", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 7
[pid    37] +++ exited with 0 +++
open("/etc/ssl/certs/ca-certificates.crt", O_RDONLY|O_LARGEFILE) = 6
+++ exited with 60 +++
/ #

主持人

mark@L-R910LPKW:~$ strace -e trace=%file -f curl -so /dev/null https://dl-cdn.alpinelinux.org/alpine/v3.17/main
execve("/usr/bin/curl", ["curl", "-so", "/dev/null", "https://dl-cdn.alpinelinux.org/a"...], 0x7fff2db4c4b0 /* 30 vars */) = 0
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=29679, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libcurl.so.4", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=677656, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libz.so.1", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=108936, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=2216304, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libnghttp2.so.14", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=166256, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libidn2.so.0", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=129096, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/librtmp.so.1", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=121864, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libssh.so.4", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=441944, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libpsl.so.5", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=75768, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libssl.so.3", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=667864, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libcrypto.so.3", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=4451632, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libgssapi_krb5.so.2", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=338648, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libldap-2.5.so.0", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=376512, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/liblber-2.5.so.0", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=63992, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libzstd.so.1", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=841808, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libbrotlidec.so.1", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=51512, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libunistring.so.2", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=1743016, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libgnutls.so.30", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=2000320, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libhogweed.so.6", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=289800, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libnettle.so.8", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=281000, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libgmp.so.10", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=526896, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libkrb5.so.3", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=827936, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libk5crypto.so.3", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=182864, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libcom_err.so.2", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=18504, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libkrb5support.so.0", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=52016, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libsasl2.so.2", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=105376, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libbrotlicommon.so.1", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=137560, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libp11-kit.so.0", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=1285888, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libtasn1.so.6", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=92312, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libkeyutils.so.1", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=22600, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libresolv.so.2", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=68552, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libffi.so.8", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=47688, ...}, AT_EMPTY_PATH) = 0
newfstatat(AT_FDCWD, "/etc/gnutls/config", 0x7ffcde3ddb00, 0) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/ssl/openssl.cnf", O_RDONLY) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=12419, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=3048928, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/share/locale/locale.alias", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=2996, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_IDENTIFICATION", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_IDENTIFICATION", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=258, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/x86_64-linux-gnu/gconv/gconv-modules.cache", O_RDONLY) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=27002, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_MEASUREMENT", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_MEASUREMENT", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=23, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_TELEPHONE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_TELEPHONE", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=47, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_ADDRESS", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_ADDRESS", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=127, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_NAME", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_NAME", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=62, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_PAPER", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_PAPER", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=34, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_MESSAGES", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_MESSAGES", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFDIR|0755, st_size=4096, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_MESSAGES/SYS_LC_MESSAGES", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=48, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_MONETARY", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_MONETARY", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=270, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_COLLATE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_COLLATE", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=1406, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_TIME", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_TIME", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=3360, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_NUMERIC", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_NUMERIC", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=50, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_CTYPE", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=353616, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/home/mark/.curlrc", O_RDONLY) = -1 ENOENT (No such file or directory)
newfstatat(AT_FDCWD, "/etc/nsswitch.conf", {st_mode=S_IFREG|0644, st_size=510, ...}, 0) = 0
newfstatat(AT_FDCWD, "/", {st_mode=S_IFDIR|0755, st_size=4096, ...}, 0) = 0
openat(AT_FDCWD, "/etc/nsswitch.conf", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=510, ...}, AT_EMPTY_PATH) = 0
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=510, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/etc/passwd", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=1948, ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "/home/mark/.curlrc", O_RDONLY) = -1 ENOENT (No such file or directory)
strace: Process 577639 attached
[pid 577639] newfstatat(AT_FDCWD, "/etc/nsswitch.conf", {st_mode=S_IFREG|0644, st_size=510, ...}, 0) = 0
[pid 577639] newfstatat(AT_FDCWD, "/etc/resolv.conf", {st_mode=S_IFREG|0644, st_size=96, ...}, 0) = 0
[pid 577639] openat(AT_FDCWD, "/etc/host.conf", O_RDONLY|O_CLOEXEC) = 7
[pid 577639] newfstatat(7, "", {st_mode=S_IFREG|0644, st_size=92, ...}, AT_EMPTY_PATH) = 0
[pid 577639] openat(AT_FDCWD, "/etc/resolv.conf", O_RDONLY|O_CLOEXEC) = 7
[pid 577639] newfstatat(7, "", {st_mode=S_IFREG|0644, st_size=96, ...}, AT_EMPTY_PATH) = 0
[pid 577639] newfstatat(7, "", {st_mode=S_IFREG|0644, st_size=96, ...}, AT_EMPTY_PATH) = 0
[pid 577639] openat(AT_FDCWD, "/etc/hosts", O_RDONLY|O_CLOEXEC) = 7
[pid 577639] newfstatat(7, "", {st_mode=S_IFREG|0644, st_size=580, ...}, AT_EMPTY_PATH) = 0
[pid 577639] openat(AT_FDCWD, "/etc/gai.conf", O_RDONLY|O_CLOEXEC) = 7
[pid 577639] newfstatat(7, "", {st_mode=S_IFREG|0644, st_size=2584, ...}, AT_EMPTY_PATH) = 0
[pid 577639] newfstatat(7, "", {st_mode=S_IFREG|0644, st_size=2584, ...}, AT_EMPTY_PATH) = 0
[pid 577639] +++ exited with 0 +++
openat(AT_FDCWD, "/etc/ssl/certs/ca-certificates.crt", O_RDONLY) = 6
newfstatat(6, "", {st_mode=S_IFREG|0644, st_size=190243, ...}, AT_EMPTY_PATH) = 0
newfstatat(AT_FDCWD, "/etc/ssl/certs/f36a1d00.0", {st_mode=S_IFREG|0644, st_size=1537, ...}, 0) = 0
openat(AT_FDCWD, "/etc/ssl/certs/f36a1d00.0", O_RDONLY) = 6
newfstatat(6, "", {st_mode=S_IFREG|0644, st_size=1537, ...}, AT_EMPTY_PATH) = 0
newfstatat(AT_FDCWD, "/etc/ssl/certs/f36a1d00.1", 0x7ffcde3dd2f0, 0) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/localtime", O_RDONLY|O_CLOEXEC) = 6
newfstatat(6, "", {st_mode=S_IFREG|0644, st_size=3552, ...}, AT_EMPTY_PATH) = 0
newfstatat(6, "", {st_mode=S_IFREG|0644, st_size=3552, ...}, AT_EMPTY_PATH) = 0
+++ exited with 35 +++
mark@L-R910LPKW:~$

mark

Asked: 2023-04-28 23:02:18 +0800 CST

为什么 xargs 不处理最后一个参数？

11

观察：

mark@L-R910LPKW:~$ echo a b | xargs -d' ' -I{} bash -c 'echo {} 1'
a 1
b
bash: line 2: 1: command not found
mark@L-R910LPKW:~$

到底是怎么回事？

mark

Asked: 2023-04-24 04:48:38 +0800 CST

如何在 diff 中使用 bash <<< 运算符？

12

请注意：

mark@L-R910LPKW:~$ diff <(echo a) <<<b
diff: missing operand after '/dev/fd/63'
diff: Try 'diff --help' for more information.
mark@L-R910LPKW:~$

我知道<(...)工作正常：

mark@L-R910LPKW:~$ diff <(echo a) <(echo b)
1c1
< a
---
> b
mark@L-R910LPKW:~$

我也知道<<<一般情况下工作正常：

mark@L-R910LPKW:~$ cat <<<a
a
mark@L-R910LPKW:~$

那么调用它的正确方法是什么diff？

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当所有证书都应该存在时，为什么从容器运行的 curl 会抱怨本地颁发者证书？

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