readlink invocation (GNU Coreutils 9.0)

12.6 readlink: Print value of a symlink or canonical file name

readlink may work in one of two supported modes:

‘Readlink mode’: readlink outputs the value of the given symbolic links. If readlink is invoked with an argument other than the name of a symbolic link, it produces no output and exits with a nonzero exit code.
‘Canonicalize mode’: readlink outputs the absolute name of the given files which contain no ., .. components nor any repeated separators (/) or symbolic links. Note the realpath command is the preferred command to use for canonicalization. See realpath invocation.

readlink [option]… file…

By default, readlink operates in readlink mode.

The program accepts the following options. Also see Common options.

‘-f’ ‘--canonicalize’

Activate canonicalize mode. If any component of the file name except the last one is missing or unavailable, readlink produces no output and exits with a nonzero exit code. A trailing slash is ignored.

‘-e’ ‘--canonicalize-existing’

Activate canonicalize mode. If any component is missing or unavailable, readlink produces no output and exits with a nonzero exit code. A trailing slash requires that the name resolve to a directory.

‘-m’ ‘--canonicalize-missing’

Activate canonicalize mode. If any component is missing or unavailable, readlink treats it as a directory.

‘-n’ ‘--no-newline’

Do not print the output delimiter, when a single file is specified. Print a warning if specified along with multiple files.

‘-s’ ‘-q’ ‘--silent’ ‘--quiet’

Suppress most error messages. On by default.

‘-v’ ‘--verbose’

Report error messages.

‘-z’ ‘--zero’

Output a zero byte (ASCII NUL) at the end of each line, rather than a newline. This option enables other programs to parse the output even when that output would contain data with embedded newlines.

The readlink utility first appeared in OpenBSD 2.1.

The realpath command without options, operates like readlink in canonicalize mode.

An exit status of zero indicates success, and a nonzero value indicates failure.