I got executable - how I will know what are obj files it buit from ?

[tvnaidu]

I got executable - any idea how I will know what are obj files it built from?.

nm or ldd doesn't show what are obj files. any other command?

[weaknessforcats]

From your makefile.

If you are using a tool like Visual Studio, it will be the object files from the source files that are in your project.

[donbock]

A no-longer-supported configuration management tool called sccs provided a utility called what. You could use this utility to print all strings of the form "@(#) text" found in the executable image. It was up to you to embed a relevant string of this sort in each source file. sccs provided keyword expansion features that made it easier to create the what strings. You also had to be careful that the string wasn't optimized out of the object file.