Gnu/coreutils/wc-invocation
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6.1 wc
: Print newline, word, and byte counts
wc
counts the number of bytes, characters, whitespace-separated
words, and newlines in each given file
, or standard input if none
are given or for a file
of ‘-
’. Synopsis:
wc [option]… [file]…
wc
prints one line of counts for each file, and if the file was
given as an argument, it prints the file name following the counts. If
more than one file
is given, wc
prints a final line
containing the cumulative counts, with the file name total
. The
counts are printed in this order: newlines, words, characters, bytes,
maximum line length.
Each count is printed right-justified in a field with at least one
space between fields so that the numbers and file names normally line
up nicely in columns. The width of the count fields varies depending
on the inputs, so you should not depend on a particular field width.
However, as a GNU extension, if only one count is printed,
it is guaranteed to be printed without leading spaces.
By default, wc
prints three counts: the newline, words, and byte
counts. Options can specify that only certain counts be printed.
Options do not undo others previously given, so
wc --bytes --words
prints both the byte counts and the word counts.
With the --max-line-length
option, wc
prints the length
of the longest line per file, and if there is more than one file it
prints the maximum (not the sum) of those lengths. The line lengths here
are measured in screen columns, according to the current locale and
assuming tab positions in every 8th column.
The program accepts the following options. Also see Common options.
- ‘
-c
’
‘--bytes
’ Print only the byte counts.
- ‘
-m
’
‘--chars
’ Print only the character counts.
- ‘
-w
’
‘--words
’ Print only the word counts.
- ‘
-l
’
‘--lines
’ Print only the newline counts.
- ‘
-L
’
‘--max-line-length
’ Print only the maximum display widths. Tabs are set at every 8th column. Display widths of wide characters are considered. Non-printable characters are given 0 width.
- ‘
--files0-from=file
’ Disallow processing files named on the command line, and instead process those named in file
file
; each name being terminated by a zero byte (ASCII NUL). This is useful when the list of file names is so long that it may exceed a command line length limitation. In such cases, runningwc
viaxargs
is undesirable because it splits the list into pieces and makeswc
print a total for each sublist rather than for the entire list. One way to produce a list of ASCII NUL terminated file names is with GNUfind
, using its-print0
predicate. Iffile
is ‘-
’ then the ASCII NUL terminated file names are read from standard input.For example, to find the length of the longest line in any
.c
or.h
file in the current hierarchy, do this:find . -name '*.[ch]' -print0 | wc -L --files0-from=- | tail -n1
An exit status of zero indicates success, and a nonzero value indicates failure.
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