Overriding C library functions, calling original

by

The linker will search the files you provide on the command line first for symbols, before it searches in libraries. This means that as soon as it sees that getline has been defined, it will no longer look for another getline symbol. This is how linkers works on all platforms.

This of course has implications for your fifth point, in that there is no possibility to call the “original” getline, as your function is the original from the point of view of the linker.

For the fifth point, you may want to look at e.g. this old answer.

More Related Contents:

  1. Removing trailing newline character from fgets() input
  2. Modulo operation with negative numbers
  3. C undefined behavior. Strict aliasing rule, or incorrect alignment? [duplicate]
  4. Order of local variable allocation on the stack
  5. What is the meaning of lines starting with a hash sign and number like ‘# 1 “a.c”‘ in the gcc preprocessor output?
  6. Adding leading underscores to assembly symbols with GCC on Win32?
  7. What is the difference between C, C99, ANSI C and GNU C?
  8. aligned malloc() in GCC?
  9. How to access C variable for inline assembly manipulation?
  10. How to check if a given file descriptor stored in a variable is still valid?
  11. Detecting 64bit compile in C
  12. How to make gcc link strong symbol in static library to overwrite weak symbol?
  13. C preprocessor: expand macro in a #warning
  14. Status of __STDC_IEC_559__ with modern C compilers
  15. Errors using ternary operator in c
  16. What is the default C -std standard version for the current GCC (especially on Ubuntu)?
  17. Check glibc version for a particular gcc compiler
  18. Why we need Clobbered registers list in Inline Assembly?
  19. What is “…” in switch-case in C code
  20. How to link to a different libc file?
  21. C code with undefined results, compiler generates invalid code (with -O3)
  22. Compiler changes printf to puts
  23. How to tell GCC to generate 16-bit code for real mode
  24. How to get the size of a C function from inside a C program or with inline assembly?
  25. Why is execstack required to execute code on the heap?
  26. gcc detect duplicate symbols/functions in static libraries
  27. GCC – no warning about an uninitialized array with -O0
  28. Order of fields when using a bit field in C
  29. How much overhead can the -fPIC flag add?
  30. conflicting types error when compiling c program using gcc

Leave a Comment