Conditional Expressions

Question 1

What is the result of this test? -a file

Answer 1

True if file exists

Question 2

What is the result of this test? -b file

Answer 2

True if file exists and is a block special file.

Question 3

What is the result of this test? -c file

Answer 3

True if file exists and is a character special file.

Question 4

What is the result of this test? -d file

Answer 4

True if file exists and is a directory.

Question 5

What is the result of this test? -e file

Answer 5

True if file exists.

Question 6

What is the result of this test? -f file

Answer 6

True if file exists and is a regular file.

Question 7

What is the result of this test? -g file

Answer 7

True if file exists and is set-group-id.

Question 8

What is the result of this test? -h file

Answer 8

True if file exists and is a symbolic link.

Question 9

What is the result of this test? -k file

Answer 9

True if file exists and its ``sticky’’ bit is set.

Question 10

What is the result of this test? -p file

Answer 10

True if file exists and is a named pipe (FIFO).

Question 11

What is the result of this test? -r file

Answer 11

True if file exists and is readable.

Question 12

What is the result of this test? -s file

Answer 12

True if file exists and has a size greater than zero.

Question 13

What is the result of this test? -t fd

Answer 13

True if file descriptor fd is open and refers to a terminal.

Question 14

What is the result of this test? -u file

Answer 14

True if file exists and its set-user-id bit is set.

Question 15

What is the result of this test? -w file

Answer 15

True if file exists and is writable.

Question 16

What is the result of this test? -x file

Answer 16

True if file exists and is executable.

Question 17

What is the result of this test? -O file

Answer 17

True if file exists and is owned by the effective user id.

Question 18

What is the result of this test? -G file

Answer 18

|True if file exists and is owned by the effective group id.

Question 19

What is the result of this test? -L file

Answer 19

True if file exists and is a symbolic link.

Question 20

What is the result of this test? -S file

Answer 20

True if file exists and is a socket.

Question 21

What is the result of this test? -N file

Answer 21

True if file exists and has been modified since it was last read.

Question 22

What is the result of this test? file1 -nt file2

Answer 22

True if file1 is newer (according to modification date) than file2, or if file1 exists and file2 does not.

Question 23

What is the result of this test? file1 -ot file2

Answer 23

True if file1 is older than file2, or if file2 exists and file1 does not.

Question 24

What is the result of this test? file1 -ef file2

Answer 24

True if file1 and file2 refer to the same device and inode numbers.

Question 25

What is the result of this test? -o optname

Answer 25

True if shell option optname is enabled.

Question 26

What is the result of this test? -z string

Answer 26

True if the length of string is zero.

Question 27

What is the result of this test? string -n string

Answer 27

True if the length of string is non-zero.

Question 28

What is the result of this test? string1 == string2 string1 = string2

Answer 28

True if the strings are equal.

Question 29

What is the result of this test? string1 != string2

Answer 29

True if the strings are not equal.

Question 30

What is the result of this test? string1 < string2

Answer 30

True if string1 sorts before string2 lexicographically.

Question 31

What is the result of this test? string1 > string2

Answer 31

True if string1 sorts after string2 lexicographically.

Question 32

What is the result of this test? arg1 OP arg2 OP is one of -eq, -ne, -lt, -le, -gt, or -ge.

Answer 32

true if arg1 is equal to, not equal to, less than, less than or equal to, greater than, or greater than or equal to arg2, respectively. Arg1 and arg2 may be positive or negative integers.