python - 管道符和ssh传文件

Question

看到可以用一条命令传输文件

gzip -c aa.txt | ssh root@192.168.1.1 " gunzip -c - > /home/bb.txt"

请问这条命令怎么理解？
还有，发现对文件夹进行这样的操作会失败，有什么办法传输文件夹么？
求指教

Answer 1

Explanation of command parameters:

gzip -h

Usage: gzip [OPTION]... [FILE]...
Compress or uncompress FILEs (by default, compress FILES in-place).

Mandatory arguments to long options are mandatory for short options too.

  -c, --stdout      write on standard output, keep original files unchanged
  -d, --decompress  decompress
  -f, --force       force overwrite of output file and compress links
  -h, --help        give this help
  -l, --list        list compressed file contents
  -L, --license     display software license
  -n, --no-name     do not save or restore the original name and time stamp
  -N, --name        save or restore the original name and time stamp
  -q, --quiet       suppress all warnings
  -r, --recursive   operate recursively on directories
  -S, --suffix=SUF  use suffix SUF on compressed files
  -t, --test        test compressed file integrity
  -v, --verbose     verbose mode
  -V, --version     display version number
  -1, --fast        compress faster
  -9, --best        compress better
    --rsyncable   Make rsync-friendly archive

With no FILE, or when FILE is -, read standard input.

gunzip -h

Usage: gzip [OPTION]... [FILE]...
Compress or uncompress FILEs (by default, compress FILES in-place).

Mandatory arguments to long options are mandatory for short options too.

  -c, --stdout      write on standard output, keep original files unchanged
  -d, --decompress  decompress
  -f, --force       force overwrite of output file and compress links
  -h, --help        give this help
  -l, --list        list compressed file contents
  -L, --license     display software license
  -n, --no-name     do not save or restore the original name and time stamp
  -N, --name        save or restore the original name and time stamp
  -q, --quiet       suppress all warnings
  -r, --recursive   operate recursively on directories
  -S, --suffix=SUF  use suffix SUF on compressed files
  -t, --test        test compressed file integrity
  -v, --verbose     verbose mode
  -V, --version     display version number
  -1, --fast        compress faster
  -9, --best        compress better
    --rsyncable   Make rsync-friendly archive

With no FILE, or when FILE is -, read standard input.

Report bugs to <bug-gzip@gnu.org>.

I don’t know what’s going on, the help documents of the two commands are the same, the developer is lazy

In other words, -c does not compress the file, but outputs it directly to standard output.

gunzip -, instead of receiving a compressed file from a file, it receives it from standard input.

|：管道
>: redirect

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Analysis of the entire command

gzip -c aa.txt | ssh root@192.168.1.1 "gunzip -c - > /home/bb.txt"

• gzip -c aa.txt: Compress the aa.txt file and output the compressed result to standard output

• ssh root@192.168.1.1 "命令"：Execute commands

on the remote machine

• Commandgunzip -c -: Decompress the file. The original compressed file is passed in from the standard input, and the output result is directly output to the standard output

• > /home/bb.txt：将标准输出重定向到文件/home/bb.txt

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Such an operation on a folder will fail

gzip does not support directory operations

Answer 2

You can either completely switch to using netcat for sending and receiving.
Or, compress it with local tar and decompress it on the opposite end.

Answer 3

Piping takes the output of the previous command as input. You can also compress it into a temporary file first and then use scp