If parsing the output of ls is dangerous because it can break on some funky characters (spaces, \n, ... ), what's the best way to know the number of files in a directory?
I usualy rely on find to avoid this parsing, but similarly, find mydir | wc -l will break for the same reasons.
I'm working on Solaris right now, but I'm looking for a answer as portable across different unices and different shells as possible.
How about this trick?
find . -maxdepth 1 -exec echo \; | wc -l
As portable as find and wc.
n+1 files on my Debian system). It also doesn't filter for regular files.
find command to your specific needs. Yes, this one includes all the directories, including . (which might be why you see the result as n+1).
find . -maxdepth 1 ! -name . -exec echo \; | wc -l; some older versions of find do not have -not.
-maxdepth is not standard (a GNU extension now also supported by a few other implementations).
In bash, without external utilities, nor loops:
shopt -s dotglob
files=(*)
echo "${#files[@]}"
In ksh, replace shopt -s dotglob by FIGNORE=.?(.).
In zsh, replace it by setopt glob_dots, or remove the shopt call and use files=(*(D)). (Or just drop the line if you don't want to include dot files.)
Portably, if you don't care about dot files:
set -- *
echo "$#"
If you do want to include dot files:
set -- *
if [ -e "$1" ]; then c=$#; else c=0; fi
set .[!.]*
if [ -e "$1" ]; then c=$((c+$#)); fi
set ..?*
if [ -e "$1" ]; then c=$((c+$#)); fi
echo "$c"
1 for an empty directory when nullglob is not enabled. In zsh, a=(*(DN));echo ${#a} with the N (nullglob) qualifier does not result in an error for an empty directory.
find . ! -name . -prune -print | grep -c /
Should be fairly portable to post-80s systems.
That counts all the directory entries except . and .. in the current directory.
To count files in subdirectories as well:
find .//. ! -name . | grep -c //
(that one should be portable even to Unix V6 (1975), since it doesn't need -prune)
find dirname ! -name dirname -prune -print). I have since been wondering if there's any particular reason to use grep -c / instead of wc -l (which is probably more commonly used for counting).
find dirname ! -name dirname doesn't work if there are other directories within that are named dirname. It's better to use find dirname/. ! -name .. wc -l counts the number of lines, file names can be made of several lines as the newline character is as valid as any in a file name.
lsTry:
ls -b1A | wc -l
The -b will escape non-printable characters, -A will show all files except . and .., and one per line (the default on a pipe, but good to be explicit).
As long as we're including higher-level scripting languages, here's a one-liner in Python:
python -c 'import os; print(len(os.listdir(os.sep)))'
Or with full 'find':
python -c 'import os; print(len([j for i in os.walk(os.sep) for j in i[1]+i[2]]))'
os.sep??? That's /, i.e. the root dir. Did you mean ".", for the current directory? You can actually remove the argument entirely (os.listdir()) and it'll automatically use the current dir.
len; use sum instead. Also, you can use unpacking instead of indexing into i. So: python -c 'import os; print(sum(len(d+f) for (_p, d, f) in os.walk(".")))'
os.walk() requires an argument. Still, os.listdir() doesn't.
os.walk() default to the current dir :)
sum(len(d)+len(f) ...
The most simple version I use all the time and never had problems with is:
ls -b1 | wc -l
\n or other funky chars (yeah, certain unices allow this).
ls -1 | wc -l fine on OpenBSD ksh
Yoc can use such construction:
I=0; for i in * ; do ((I++)); done ; echo $I
But I'm afraid, you can cath error like Argument list too long. in case you have too many files in directory. However I tested it on directory with 10 billion files, and it worked well.
*.
gnu find . -maxdepth 1 -type f | wc -l
for.
Have you considered perl, which should be relatively portable?
Something like:
use File::Find;
$counter = 0;
sub wanted {
-f && ++$counter
}
find(\&wanted, @directories_to_search);
print "$counter\n";
Try this => Using ls with -i ( for node number ) & -F (appends directory name with '/' ) options.
ls -ilF | egrep -v '/' | wc -l
With a perl one-liner (reformatted for readability):
perl -e 'opendir($dh, ".");
while ( readdir($dh) ) {$count++};
closedir $dh;
print "$count\n";'
or
perl -e 'opendir($dh, ".");
@files = readdir($dh);
closedir $dh;
print $#files+1,"\n";'
You can use perl functions that modify arrays like grep or map with the second version. See perldoc -f readdir for an example using grep.
In addition to the find-based answer proposed by Stéphane, here is a POSIX-compliant answer based on ls:
ls -qf | tail -n +3 | wc -l
findwill get you number of files recursively (use-maxdepth 1if you don't want that.find mydir -maxdepth 1 -type f -printf \\n | wc -lshould handle the special characters in the filename, as they are never printed in the first place.