Modify file name {fname} according to {mods}. {mods} is a string of characters like it is used for file names on the command line. See filename-modifiers. Example:

:echo fnamemodify("main.c", ":p:h")

results in:

/home/user/vim/vim/src

If {mods} is empty or an unsupported modifier is used then {fname} is returned. When {fname} is empty then with {mods} ":h" returns ".", so that :cd can be used with it. This is different from expand('%:h') without a buffer name, which returns an empty string. Note: Environment variables don't work in {fname}, use expand() first then.

Can also be used as a method:

GetName()->fnamemodify(':p:h')