File and Directory Selection (GNU Grep 3.7)
2.1.6 File and Directory Selection
Process a binary file as if it were text; this is equivalent to the ‘
If a file’s data or metadata indicate that the file contains binary data, assume that the file is of type
type. Non-text bytes indicate binary data; these are either output bytes that are improperly encoded for the current locale (see Environment Variables), or null input bytes when the
--null-data) option is not given (see Other Options).
grepsuppresses output after null input binary data is discovered, and suppresses output lines that contain improperly encoded data. When some output is suppressed,
grepfollows any output with a one-line message saying that a binary file matches.
grepdiscovers null input binary data it assumes that the rest of the file does not match; this is equivalent to the
grepprocesses binary data as if it were text; this is equivalent to the
grepmay treat non-text bytes as line terminators even without the
--null-data) option. This means choosing ‘
binary’ versus ‘
text’ can affect whether a pattern matches a file. For example, when
binary’ the pattern ‘
q$’ might match ‘
q’ immediately followed by a null byte, even though this is not matched when
text’. Conversely, when
binary’ the pattern ‘
.’ (period) might not match a null byte.
--binary-files=text) option might output binary garbage, which can have nasty side effects if the output is a terminal and if the terminal driver interprets some of it as commands. On the other hand, when reading files whose text encodings are unknown, it can be helpful to use
-aor to set ‘
LC_ALL='C'’ in the environment, in order to find more matches even if the matches are unsafe for direct display.
If an input file is a device, FIFO, or socket, use
actionto process it. If
read’, all devices are read just as if they were ordinary files. If
skip’, devices, FIFOs, and sockets are silently skipped. By default, devices are read if they are on the command line or if the
--dereference-recursive) option is used, and are skipped if they are encountered recursively and the
--recursive) option is used. This option has no effect on a file that is read via standard input.
If an input file is a directory, use
actionto process it. By default,
read’, which means that directories are read just as if they were ordinary files (some operating systems and file systems disallow this, and will cause
grepto print error messages for every directory or silently skip them). If
skip’, directories are silently skipped. If
grepreads all files under each directory, recursively, following command-line symbolic links and skipping other symlinks; this is equivalent to the
Skip any command-line file with a name suffix that matches the pattern
glob, using wildcard matching; a name suffix is either the whole name, or a trailing part that starts with a non-slash character immediately after a slash (‘
/’) in the name. When searching recursively, skip any subfile whose base name matches
glob; the base name is the part after the last slash. A pattern can use ‘
?’, and ‘
]’ as wildcards, and
\to quote a wildcard or backslash character literally.
Skip files whose name matches any of the patterns read from
file(using wildcard matching as described under
Skip any command-line directory with a name suffix that matches the pattern
glob. When searching recursively, skip any subdirectory whose base name matches
glob. Ignore any redundant trailing slashes in
Process a binary file as if it did not contain matching data; this is equivalent to the ‘
Search only files whose name matches
glob, using wildcard matching as described under
--exclude. If contradictory
--excludeoptions are given, the last matching one wins. If no
--excludeoptions match, a file is included unless the first such option is
For each directory operand, read and process all files in that directory, recursively. Follow symbolic links on the command line, but skip symlinks that are encountered recursively. Note that if no file operand is given, grep searches the working directory. This is the same as the ‘
For each directory operand, read and process all files in that directory, recursively, following all symbolic links.