basename - strip file name affixes
basename [ -d ] string [ suffix ]
Basename deletes any prefix ending in slash (/) and the suffix, if
present in string, from string, and prints the result on the standard
output.
The -d option instead prints the directory component, that is, string
up to but not including the final slash. If the string contains no
slash, a period and newline are printed.
/src/cmd/basename.c
BASENAME(1)