ls.o - list directory contents as my summer project in linux programming course refer to: http://man7.org/linux/man-pages/
Adolphin Huang
ls [OPTION]... [FILE]...
"sudo apt install libbsd-dev "to install BSD library fisrt
List information about the FILEs (the current directory by default) with one file per line. Sort entries alphabetically if no option below is specified:
-a, --all
do not ignore entries starting with .
-A, --almost-all
do not list implied . and ..
-c with -lt: sort by, and show, ctime (time of last modification
of file status information); with -l: show ctime and sort by
name; otherwise: sort by ctime, newest first
-d, --directory
list directories themselves, not their contents
-f do not sort, enable -aU, disable -ls --color
-F, --classify
append indicator (one of */@|) to entries
-g like -l, but do not list owner
-G, --no-group
in a long listing, don't print group names
-h, --human-readable
with -l and/or -s, print human readable sizes (e.g., 1K 234M
2G)
-i, --inode
print the index number of each file
-k, --kibibytes
default to 1024-byte blocks for disk usage
-l use a long listing format
-n, --numeric-uid-gid
like -l, but list numeric user and group IDs
-o like -l, but do not list group information
-p, --indicator-style=slash
append / indicator to directories
-Q, --quote-name
enclose entry names in double quotes
-r, --reverse
reverse order while sorting
-R, --recursive
list subdirectories recursively
-s, --size
print the allocated size of each file, in blocks
-S sort by file size, largest first
-t sort by modification time, newest first
-u with -lt: sort by, and show, access time; with -l: show access
time and sort by name; otherwise: sort by access time, newest
first
-U do not sort; list entries in directory order