Shell condition Test Statement three methods

1, test-f file 2, [-F file] 3, [[-F file]]

[-F file1-a-F file2] logic with [-f file1-o-F file2] logic or [-f file1] && [-f file2] the same as a string operation best double quotes such as-n-z = = = And a space is added to both sides of the equals sign .

# # #man Test

(EXPRESSION)
EXPRESSION is True

! EXPRESSION
EXPRESSION is False

Expression1-a EXPRESSION2
Both EXPRESSION1 and EXPRESSION2 are true

Expression1-o EXPRESSION2
Either EXPRESSION1 or EXPRESSION2 is true

-N STRING
The length of STRING is nonzero

String equivalent To-n string

-Z STRING
The length of STRING is zero

STRING1 = STRING2
The strings is equal

STRING1! = STRING2
The strings is not equal

Integer1-eq INTEGER2
INTEGER1 is equal to INTEGER2

Integer1-ge INTEGER2
INTEGER1 is greater than or equal to INTEGER2

INTEGER1-GT INTEGER2
INTEGER1 is greater than INTEGER2

Integer1-le INTEGER2
INTEGER1 is less than or equal to INTEGER2

Integer1-lt INTEGER2
INTEGER1 is less than INTEGER2

Integer1-ne INTEGER2
INTEGER1 isn't equal to INTEGER2

File1-ef FILE2
FILE1 and FILE2 have the same device and inode numbers

File1-nt FILE2
FILE1 is newer (modification date) than FILE2

File1-ot FILE2
FILE1 is older than FILE2

-B FILE
FILE exists and is block special

-C FILE
FILE exists and is character special

-D FILE
FILE exists and is a directory

-E FILE
FILE exists

-F FILE
File exists and is a regular file

-G FILE
FILE exists and is Set-group-id

-G FILE
FILE exists and is owned by the effective group ID

-H FILE
FILE exists and is a symbolic link (same as-l)

-K FILE
FILE exists and have its sticky bit set

-L FILE
FILE exists and is a symbolic link (same as-h)

-O FILE
FILE exists and is owned by the effective user ID

-P FILE
FILE exists and is a named pipe

-R FILE
FILE exists and Read permission is granted

-S FILE
FILE exists and has a size greater than zero

-S FILE
FILE exists and is a socket

-T FD file descriptor FD is opened on a terminal

-U FILE
FILE exists and its set-user-id bit is set

-W FILE
FILE exists and write permission is granted

-X FILE
FILE exists and execute (or search) permission is granted

Except for-h and-l, all file-related tests dereference symbolic links. Beware that parentheses need to be
Escaped (e.g., by backslashes) for shells. INTEGER may also be-l STRING, which evaluates to the length of
STRING.

Shell condition Test Statement three methods