I am a newcomer who just started learning C language. When I was writing C code using CLion, I could access it by Ctrl + mouse click .
I'm calling the method inside the header function. For example, if I use printf , I can access the stdio.h file, which can be seen at line 332 extern int printf (const char * ___, RESTRICT, format,...) ; .
But if I want to see the details of this method
I can't see it. According to Navigate in the code structure
Use Ctrl+Alt+Home to switch. But the IDE prompts No related file .
How can I get the source code to call a method? I want to learn from the good experiences of others by looking at their implementation logic in their libraries
Thank you for your review. I would really appreciate it if you could help me.
Even if most of GNU/Linux software is open source, it is not installed (in source code form) by default on your computer.
Regarding C programming, see Modern C (and the C11 standard n1570) and read the documentation of your C compiler (perhaps GCC or Clang, or simpler ones like nwcc or tinycc), your linker (probably binutils), your build automation tool (e.g. GNU make or ninja or cmake). Enable all warnings and DWARF debug info, so if using GCC compile with at least gcc -Wall -Wextra -g; then improve your C code to get no warnings. Once you have debugged your C source code (using GDB and perhaps valgrind), add optimization flags such as -O2. Order of arguments to gcc matters!
Consider, for some tasks, generating some of your C code (perhaps some #include-d header file) with tools like GNU bison, ANTLR, SWIG, RPCGEN, AWK, GUILE, GPP, GNU m4, GNU autoconf - or your own program or script.
I want to learn from the good experiences of others by looking at their implementation logic in their libraries
For examples, see GNU libc or musl-libc, and the Linux kernel (and others: GTK, PostGreSQL, sqlite, GUILE, etc.... including many open source programs mentionned in this answer) and look also on websites like github, gitlab, sourceforge
Read also Advanced Linux Programming and syscalls(2). See also http://linuxfromscratch.org/
In 2020, a recent GCC compiler happens to handle specially calls to printf when asked to optimize. See the softwareheritage and Frama-C projects.
In some cases, consider accepting plugins in your program with dlopen(3) and dlsym(3) (see also elf(5) and How to Write Shared Libraries). You might even generate some code at runtime with libraries like libgccjit (or generate C code at runtime, then compile it as a plugin, and load it; such an approach is called metaprogramming and is related to partial evaluation; see also the blog of the late J.Pitrat for more insights).
Of course, you need tools to navigate in source code. Consider using GNU emacs combined with GNU grep for that, or some other source navigator. For large programs of millions of source code lines, consider writing your own GCC plugin to understand them.
Use also tools like strace(1) and GDB to understand the dynamic behavior of programs.
You could be interested by ACM conference papers also.
For your own source code, consider using some version control tool such as git. Of course read its documentation. And use LibreOffice, Lout or LaTeX, MarkDown (perhaps combined with inkscape or diagrams for figures) to write the documentation of your software.
In some cases, you might consider generating parts of the documentation from parts of your source code (e.g. using literate programming techniques like nuweb or documentation generators like doxygen).