wget - N은 timestemp가 변경되지 않더라도 항상 파일을 다시 다운로드합니다.

Question

타임스탬프가 변경된 파일을 다운로드하는 방법에 대해 이 사이트를 찾았습니다.

https://www.gnu.org/software/wget/manual/html_node/Time_002dStamping-Usage.html

나는 그것을 시도했지만 wget은 항상 그것을 다시 다운로드합니다. 그러나 타임스탬프는 변경되지 않습니다. 내가 여기서 무엇을 얻지 못합니까?

[tom@machine Downloads]$ ll
total 48536
-rw-r--r-- 1 tom students 49693179 Apr  5 07:22 assembly_summary_genbank.txt
[tom@machine Downloads]$ wget -N ftp://ftp.ncbi.nlm.nih.gov/genomes/genbank/assembly_summary_genbank.txt
--2018-04-05 18:24:42--  ftp://ftp.ncbi.nlm.nih.gov/genomes/genbank/assembly_summary_genbank.txt
           => ‘.listing’
Resolving ftp.ncbi.nlm.nih.gov (ftp.ncbi.nlm.nih.gov)... 165.112.9.229, 2607:f220:41e:250::11
Connecting to ftp.ncbi.nlm.nih.gov (ftp.ncbi.nlm.nih.gov)|165.112.9.229|:21... connected.
Logging in as anonymous ... Logged in!
==> SYST ... done.    ==> PWD ... done.
==> TYPE I ... done.  ==> CWD (1) /genomes/genbank ... done.
==> PASV ... done.    ==> LIST ... done.

.listing                                                 [ <=>                                                                                                                  ]   1.11K  --.-KB/s    in 0.002s  

2018-04-05 18:24:44 (449 KB/s) - ‘.listing’ saved [1133]

Removed ‘.listing’.
--2018-04-05 18:24:44--  ftp://ftp.ncbi.nlm.nih.gov/genomes/genbank/assembly_summary_genbank.txt
           => ‘assembly_summary_genbank.txt’
==> CWD not required.
==> SIZE assembly_summary_genbank.txt ... 49693179
==> PASV ... done.    ==> RETR assembly_summary_genbank.txt ... done.
Length: 49693179 (47M) (unauthoritative)

assembly_summary_genbank.txt                         100%[=====================================================================================================================>]  47.39M  5.44MB/s    in 9.1s    

2018-04-05 18:24:54 (5.20 MB/s) - ‘assembly_summary_genbank.txt’ saved [49693179]

[tom@machine Downloads]$ ll
total 48536
-rw-r--r-- 1 tom students 49693179 Apr  5 07:22 assembly_summary_genbank.txt