程序員的3個美德，其中之一就是懶惰，凡是不影響大局的代碼警告我都懶得去解決，比如每次啓動R語言都會有：
Type 'demo()' for some demos, 'help()' for on-line help, or 'help.start()' for an HTML browser interface to help. Type 'q()' to quit R. During startup - Warning messages: 1: Setting LC_CTYPE failed, using "C" 2: Setting LC_COLLATE failed, using "C" 3: Setting LC_TIME failed, using "C" 4: Setting LC_MESSAGES failed, using "C" 5: Setting LC_MONETARY failed, using "C"
這樣的警告信息，因爲不影響R的繼續使用，所以我通常是視而不見。
但是在安裝一個R包的時候終於開始報錯了，而且錯誤信息表明是之前的這個警告：
> devtools::install_github("mskcc/pctGCdata")
Downloading GitHub repo mskcc/pctGCdata@master
tar: Failed to set default locale
tar: Failed to set default locale
During startup - Warning messages:
1: Setting LC_CTYPE failed, using "C"
2: Setting LC_TIME failed, using "C"
3: Setting LC_MESSAGES failed, using "C"
4: Setting LC_MONETARY failed, using "C"
v checking for file '/private/var/folders/2x/l4fzfvy17gz94j1sz6klhyjh0000gn/T/RtmpH50TBq/remotes4f18707324d6/mskcc-pctGCdata-c199831/DESCRIPTION' ...
- preparing 'pctGCdata':
v checking DESCRIPTION meta-information ...
- installing the package to process help pages
- saving partial Rd database (2m 1.2s)
- checking for LF line-endings in source and make files and shell scripts
- checking for empty or unneeded directories
- looking to see if a 'data/datalist' file should be added
- building 'pctGCdata_0.2.0.tar.gz'
Error: (converted from warning) Setting LC_CTYPE failed, using "C"
Execution halted
Error in i.p(...) :
(converted from warning) installation of package '/var/folders/2x/l4fzfvy17gz94j1sz6klhyjh0000gn/T//RtmpH50TBq/file4f18184bb97f/pctGCdata_0.2.0.tar.gz' had non-zero exit status所以迫使我不得不去搜索解決方案，查到：
https://stackoverflow.com/questions/9689104/installing-r-on-mac-warning-messages-setting-lc-ctype-failed-using-c 這樣的MAC解決方案，所以我打開我的mac終端，去敲入代碼：
defaults write org.R-project.R force.LANG en_US.UTF-8
然後重啓R語言，再次進入代碼編輯器，重新安裝這個R包，解決問題！！！
成功安裝信息如下：
> devtools::install_github("mskcc/pctGCdata")
Downloading GitHub repo mskcc/pctGCdata@master
✔ checking for file ‘/private/var/folders/2x/l4fzfvy17gz94j1sz6klhyjh0000gn/T/RtmpUXwAea/remotes51b3692788c/mskcc-pctGCdata-c199831/DESCRIPTION’ ...
─ preparing ‘pctGCdata’:
✔ checking DESCRIPTION meta-information ...
─ installing the package to process help pages
─ saving partial Rd database (2m 3.6s)
─ checking for LF line-endings in source and make files and shell scripts
─ checking for empty or unneeded directories
─ looking to see if a ‘data/datalist’ file should be added
─ building ‘pctGCdata_0.2.0.tar.gz’
* installing *source* package ‘pctGCdata’ ...
** R
** data
*** moving datasets to lazyload DB
** byte-compile and prepare package for lazy loading
** help
*** installing help indices
** building package indices
** testing if installed package can be loaded
* DONE (pctGCdata)很有趣，爲什麼之前沒有啥影響的警告在這個時候就成了致命的錯誤呢？
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