Tell me what the compiler does here?

Please tell me what it does?

$ ar -r libsldap.a开发者_如何学JAVA

"Teach a man to fish", I say:

> man ar

[...]
DESCRIPTION
       The GNU ar program creates, modifies, and extracts from archives.  An
       archive is a single file holding a collection of other files in a
       structure that makes it possible to retrieve the original individual
       files (called members of the archive).
[...]

man is your friend.

ar -r libsldap.a list-of-object-files

This line creates Linux static library, which is actually archive file that contains one or more .o files. Compiler is used previously to create these .o files.

http://www.linux.org/docs/ldp/howto/Program-Library-HOWTO/static-libraries.html