Gnu/coreutils/File-characteristic-tests

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16.3.3 File characteristic tests

These options test other file characteristics.

-e file

True if file exists.

-s file

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

file1 -nt file2

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

file1 -ot file2

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

file1 -ef file2

True if file1 and file2 have the same device and inode numbers, i.e., if they are hard links to each other.

-N file

True if file exists and has been modified (mtime) since it was last read (atime).