Is this possible to customize printf?

by

Sorry, but some answers are incorrect on Linux with Glibc

On Linux with a GNU Glibc, you can customize printf: you would call
register_printf_function to e.g. define the meaning of %Y in your printf format strings.

However, this behavior is Glibc specific, and might even become obsolete… I’m not sure I would recommend this approach!

If coding in C++, the C++ stream library has manipulators which you could extend, and you can also overload for your types the operator << etc.

added in february 2018

You could consider writing a GCC plugin helping that (and improving the typechecking of some extended printf). It won’t be easy (probably a few weeks or months of work), and it would be GCC version specific (not the same plugin code for GCC 7 and GCC 8). you might add some specific #pragma to inform your plugin about extra control string specifiers like your %Y and the type expected for them. Your plugin should change the handling of format attribute (perhaps in gcc/tree.c)

More Related Contents:

  1. building a .so that is also an executable
  2. How to compile my own glibc C standard library from source and use it?
  3. Writing to a closed, local TCP socket not failing
  4. Force free() to return malloc memory back to OS
  5. Why does forking my process cause the file to be read infinitely
  6. Where are syscalls located in glibc source
  7. multiple threads able to get flock at the same time
  8. What are the flags and macros in a Makefile? [closed]
  9. How to write a signal handler to catch SIGSEGV?
  10. Where is the itoa function in Linux?
  11. Where is PATH_MAX defined in Linux?
  12. Why do we cast sockaddr_in to sockaddr when calling bind()?
  13. How to set the name of a thread in Linux pthreads?
  14. “undefined reference to `pow'” even with math.h and the library link -lm [duplicate]
  15. How Can I debug a C program on Linux?
  16. How to use POSIX semaphores on forked processes in C?
  17. Pipe buffer size is 4k or 64k?
  18. How to wait for exit of non-children processes
  19. Compiler using local variables without adjusting RSP
  20. How can I convert a file pointer ( FILE* fp ) to a file descriptor (int fd)?
  21. How to access mmaped /dev/mem without crashing the Linux kernel?
  22. How to solve “ptrace operation not permitted” when trying to attach GDB to a process?
  23. How can a shared library (.so) call a function that is implemented in its loader code?
  24. Memory usage of current process in C
  25. fd leak, custom Shell
  26. How can I include a needed C library using GCC?
  27. _GNU_SOURCE and __USE_GNU
  28. How do you write a C program to execute another program?
  29. Pipes, dup2 and exec()
  30. How to print exact value of the program counter in C

Leave a Comment