Bash - 3 • My Notes

Operators: Files#

Operator	Tests Whether	Operator	Tests Whether
-e	File exists	-s	File is not zero size
-f	File is a regular file
-d	File is a directory	-r	File has read permission
-h	File is a symbolic link	-w	File has write permission
-L	File is a symbolic link	-x	File has execute permission
-b	File is a block device
-c	File is a character device	-g	sgid flag set
-p	File is a pipe	-u	suid flag set
-S	File is a socket	-k	“sticky bit” set
-t	File is associated with a terminal
-N	File modified since it was last read	F1 -nt F2	File F1 is newer than F2 *
-O	You own the file	F1 -ot F2	File F1 is older than F2 *
-G	Group id of file same as yours	F1 -ef F2	Files F1 and F2 are hard links to the same file *
!	NOT (inverts sense of above tests)

Sample#


function is_symbolic_link(){
    echo "Is the file $1  a symbolic link?";

    if  [ -f $1 ] && [ -h $1 ]; 
    then
        echo 'true' ; 
    else 
        echo 'false'; 
    fi;
}

function is_file_empty () {

    echo "Is the file $1  empty?";

    if  [ -f $1 ] && [ ! -s $1 ]; 
    then
        echo 'true' ; 
    else 
        echo 'false'; 
    fi;
}