The document discusses the history and future plans of rurema, the Japanese Ruby reference manual project. It began as a wiki to document Ruby 1.6-1.8, and later the rurema project was started to improve the documentation. Current plans include converting the documentation from the original RD syntax to Markdown to improve accessibility and contributions. Other goals include cleaning up unused files, improving usage documentation, and integrating with other Ruby tools like RBS and IRB. Long term plans could include i18n support, but English will likely remain the basis.
This document summarizes several useful but lesser known features in Ruby, as presented by Kazuhiro Nishiyama of Ruby Kagoshima Conference 01 in 2019. It covers string and hash methods like String#undump, Hash#transform_*, Hash#to_h with a block, and string manipulation methods such as String#prepend and String#delete. Regular expression features like Regexp.union and string matching methods like String#start_with? are also introduced.
22. poweroff
[ 169.345939] systemd-shutdown[1]: Powering off.
[ 169.348326] reboot: Power down
なぜか poweroff をしても上の行までで qemu-
system-riscv64 が終了せずに止まってしまう
C-a x で終了
ホスト側が amd64 の Ubuntu 20.04 だと問題
なし
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23. 困りごと
debian@debian-riscv64:~$ echo 'int main(){return 0;}' | gcc -xc -
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crti.o: mis-matched ISA version 2.0 for 'i' extension, the output version is 2.1
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crti.o: mis-matched ISA version 2.0 for 'a' extension, the output version is 2.1
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crti.o: mis-matched ISA version 2.0 for 'f' extension, the output version is 2.2
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crti.o: mis-matched ISA version 2.0 for 'd' extension, the output version is 2.2
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtbeginS.o: mis-matched ISA version 2.0 for 'i' extension, the output version is 2.1
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtbeginS.o: mis-matched ISA version 2.0 for 'a' extension, the output version is 2.1
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtbeginS.o: mis-matched ISA version 2.0 for 'f' extension, the output version is 2.2
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtbeginS.o: mis-matched ISA version 2.0 for 'd' extension, the output version is 2.2
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtendS.o: mis-matched ISA version 2.0 for 'i' extension, the output version is 2.1
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtendS.o: mis-matched ISA version 2.0 for 'a' extension, the output version is 2.1
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtendS.o: mis-matched ISA version 2.0 for 'f' extension, the output version is 2.2
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtendS.o: mis-matched ISA version 2.0 for 'd' extension, the output version is 2.2
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtn.o: mis-matched ISA version 2.0 for 'i' extension, the output version is 2.1
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtn.o: mis-matched ISA version 2.0 for 'a' extension, the output version is 2.1
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtn.o: mis-matched ISA version 2.0 for 'f' extension, the output version is 2.2
/usr/bin/ld: warning: /usr/lib/gcc/riscv64-linux-gnu/11/crtn.o: mis-matched ISA version 2.0 for 'd' extension, the output version is 2.2
debian@debian-riscv64:~$
なぜかリンクで警告がでる
(/usr/bin/ld: warning: /usr/lib/gcc/
riscv64-linux-gnu/11/crti.o: mis-matched
ISA version 2.0 for 'i' extension, the
output version is 2.1 など)
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