alhelal@VimLaTeX:~$ pdflatex -v
pdfTeX 3.14159265-2.6-1.40.18 (TeX Live 2017/Debian)
kpathsea version 6.2.3
Copyright 2017 Han The Thanh (pdfTeX) et al.
There is NO warranty. Redistribution of this software is
covered by the terms of both the pdfTeX copyright and
the Lesser GNU General Public License.
For more information about these matters, see the file
named COPYING and the pdfTeX source.
Primary author of pdfTeX: Han The Thanh (pdfTeX) et al.
Compiled with libpng 1.6.34; using libpng 1.6.34
Compiled with zlib 1.2.11; using zlib 1.2.11
Compiled with poppler version 0.62.0
alhelal@VimLaTeX:~$
alhelal@VimLaTeX:/usr/local/texlive/2018$ ls
bin install-tl LICENSE.TL readme-txt.dir texmf.cnf texmf-dist
doc.html install-tl.log README README.usergroups texmfcnf.lua texmf-var
index.html LICENSE.CTAN readme-html.dir release-texlive.txt texmf-config tlpkg
alhelal@VimLaTeX:/usr/local/texlive/2018$
$ whereis pdflatex
pdflatex: /usr/bin/pdflatex /usr/local/texlive/2018/bin/x86_64-linux/pdflatex /usr/share/man/man1/pdflatex.1.gz
我还从 ubuntu 软件中心安装了 TeXstudio、Texmaker 和 Kile。
我猜这些软件安装了pdflatex 2017，所以系统首先找到pdflatex 2017，而不是pdflatex 2018。
如何在 CLI 和其他使用 pdflatex 的软件中将 pdflatex 2018 用作默认值？我在 ubuntu 18.04 中。