Print a list of "full" relative paths of all the files present in a directory and in its sub-directories

The most straightforward option would be find:

$ cd /usr/lib; find .
.
./libxcb-icccm.so.4.0.0
./libbz2.so.1.0.6
./libdca.so.0
./libxcb-composite.so
./libyajl.so
./libswscale.so
./libxvidcore.so.4.3
./libjasper.so.1
./libdrm_intel.so.1
...

It has various tests for filtering such as:

• -type to filter based on type (regular file f, directory d, etc.)
• -mindepth and -maxdepth to set the depths to which find should search (not really tests as such)
• -name and -path to filter based on filename and path, supporting wildcards.
• and a lot of other tests, for permissions, ownership, times, etc.

It offers a variety of output formats, using the -printf option.

Depending on the shell and the options enabled, you can also use globbing for this purpose. For example, in bash:

$ shopt -s globstar; printf "%s\n" **
accountsservice
accountsservice/accounts-daemon
aisleriot
aisleriot/ar-cards-renderer
aisleriot/guile
aisleriot/guile/2.0
aisleriot/guile/2.0/accordion.go
aisleriot/guile/2.0/agnes.go
aisleriot/guile/2.0/aisleriot
aisleriot/guile/2.0/aisleriot/api.go
...

And in zsh:

$ printf "%s\n" **/*
accountsservice
accountsservice/accounts-daemon
aisleriot
aisleriot/ar-cards-renderer
aisleriot/guile
aisleriot/guile/2.0
aisleriot/guile/2.0/accordion.go
aisleriot/guile/2.0/agnes.go
aisleriot/guile/2.0/aisleriot
aisleriot/guile/2.0/aisleriot/api.go
...