Is there a bash command which counts files

Question

Is there a bash command which counts the number of files that match a pattern   For example  I want to get the count of all files in a directory which match this pattern  log

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You can define such a command easily  using a shell function  This method does not require any external program and does not spawn any child process  It does not attempt hazardous ls parsing and handles    special    characters  whitespaces  newlines  backslashes and so on  just fine  It only relies on the file name expansion mechanism provided by the shell  It is compatible with at least sh  bash and zsh   The line below defines a function called count which prints the number of arguments with which it has been called   count     echo         Simply call it with the desired pattern   count log    For the result to be correct when the globbing pattern has no match  the shell option nullglob  or failglob     which is the default behavior on zsh  must be set at the time expansion happens  It can be set like this   shopt -s nullglob      for sh   bash setopt nullglob        for zsh   Depending on what you want to count  you might also be interested in the shell option dotglob   Unfortunately  with bash at least  it is not easy to set these options locally  If you don   t want to set them globally  the most straightforward solution is to use the function in this more convoluted manner     shopt -s nullglob   shopt -u failglob   count log      If you want to recover the lightweight syntax count log   or if you really want to avoid spawning a subshell  you may hack something along the lines of     sh   bash    the alias is expanded before the globbing pattern  so we   can set required options before the globbing gets expanded    and restore them afterwards  count         eval    count saved shopts      unset  count saved shopts     echo      alias count        count saved shopts    shopt -p nullglob failglob       shopt -s nullglob     shopt -u failglob     count      As a bonus  this function is of a more general use  For instance   count a  b             count files which match either a  or b  count   jobs -ps       count stopped jobs  sh   bash    By turning the function into a script file  or an equivalent C program   callable from the PATH  it can also be composed with programs such as find and xargs   find   FIND OPTIONS  -exec count            count results of a search

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ls -1 log    wc -l   Which means list one file per line and then pipe it to word count command with parameter switching to count lines

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You can do this safely  i e  won t be bugged by files with spaces or  n in their name  with bash     shopt -s nullglob   logfiles    log    echo    logfiles       You need to enable nullglob so that you don t get the literal   log in the  logfiles array if no files match   See How to  undo  a  set -x   for examples of how to safely reset it

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I ve given this answer a lot of thought  especially given the don apos t-parse-ls stuff  At first  I tried    lt WARNING  DID NOT WORK gt   du --inodes --files0-from  lt  find   -maxdepth 1 -type f -print0    awk   sum  int  1  END print sum      lt  WARNING  DID NOT WORK gt   which worked if there was only a filename like  touch   w nlf aa    but failed if I made a filename like this  touch   firstline n3 and some other n1 n2 texciting n86stuff jpg    I finally came up with what I m putting below  Note I was trying to get a count of all files in the directory  not including any subdirectories   I think it  along with the answers by  Mat and  Dan Yard   as well as having at least most of the requirements set out by  mogsie  I m not sure about memory   I think the answer by  mogsie is correct  but I always try to stay away from parsing ls unless it s an extremely specific situation   awk -F  0    print NF-1    lt   lt  find   -maxdepth 1 -type f -print0    awk   sum   1 END print sum     More readably   awk -F  0    print NF-1    lt       lt  find   -maxdepth 1 -type f -print0          awk   sum   1 END print sum     This is doing a find specifically for files  delimiting the output with a null character  to avoid problems with spaces and linefeeds   then counting the number of null characters  The number of files will be one less than the number of null characters  since there will be a null character at the end   To answer the OP s question  there are two cases to consider  1  Non-recursive search   awk -F  0    print NF-1    lt       lt  find   -maxdepth 1 -type f -name  log   -print0          awk   sum   1 END print sum     2  Recursive search  Note that what s inside the -name parameter might need to be changed for slightly different behavior  hidden files  etc     awk -F  0    print NF-1    lt       lt  find   -type f -name  log   -print0          awk   sum   1 END print sum     If anyone would like to comment on how these answers compare to those I ve mentioned in this answer  please do     Note  I got to this thought process while getting this answer

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This simple one-liner should work in any shell  not just bash   ls -1q log    wc -l   ls -1q will give you one line per file  even if they contain whitespace or special characters such as newlines   The output is piped to wc -l  which counts the number of lines

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To count everything just pipe ls to word count line   ls   wc -l   To count with pattern  pipe to grep first   ls   grep log   wc -l

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For a recursive search   find   -type f -name    log  -printf x   wc -c   wc -c will count the number of characters in the output of find  while -printf x tells find to print a single x for each result   For a non-recursive search  do this   find   -maxdepth 1 -type f -name    log  -printf x   wc -c

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An important comment   not enough reputation to comment   This is BUGGY   ls -1q some pattern   wc -l   If shopt -s nullglob happens to be set  it prints the number of ALL regular files  not just the ones with the pattern  tested on CentOS-8 and Cygwin   Who knows what other meaningless bugs does ls have   This is CORRECT and much faster   shopt -s nullglob  files  some pattern   echo    files        It does the expected job   And the running times differ  The 1st  0 006 on CentOS  and 0 083 on Cygwin  in case it is used with care   The 2nd  0 000 on CentOS  and 0 003 on Cygwin

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This can be done with standard POSIX shell grammar  Here is a simple count entries function     usr bin env sh  count entries         Emulating Bash nullglob      If argument 1 is not an existing entry   if     -e  quot  1 quot          argument is a returned pattern       then shift it out     then shift   fi   echo       for a compact definition  count entries        -e  quot  1 quot    amp  amp shift echo       Featured POSIX compatible file counter by type     usr bin env sh  count files     Count the file arguments matching the file operator   Synopsys    count files operator FILE         Arguments     1  The file operator     Allowed values      -a FILE    True if file exists      -b FILE    True if file is block special      -c FILE    True if file is character special      -d FILE    True if file is a directory      -e FILE    True if file exists      -f FILE    True if file exists and is a regular file      -g FILE    True if file is set-group-id      -h FILE    True if file is a symbolic link      -L FILE    True if file is a symbolic link      -k FILE    True if file has its  sticky  bit set      -p FILE    True if file is a named pipe      -r FILE    True if file is readable by you      -s FILE    True if file exists and is not empty      -S FILE    True if file is a socket      -t FD      True if FD is opened on a terminal      -u FILE    True if the file is set-user-id      -w FILE    True if the file is writable by you      -x FILE    True if the file is executable by you      -O FILE    True if the file is effectively owned by you      -G FILE    True if the file is effectively owned by your group      -N FILE    True if the file has been modified since it was last read        The files arguments   Output      The number of matching files   Return      1  Unknown file operator     operator  1   shift   case  operator in     - abcdefghLkprsStuwxOGN         for arg  do           If file is not of required type         if   test  quot  operator quot   quot  arg quot   then             Shift it out           shift         fi       done       echo                          printf  Invalid file operator   s n   quot  operator quot   gt  amp 2       return 1            esac    count files  quot    quot   Example usages  count files -f log  txt count files -d datadir

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Lots of answers here  but some don t take into account   file names with spaces  newlines  or control characters in them file names that start with hyphens  imagine a file called -l  hidden files  that start with a dot  if the glob was   log instead of log  directories that match the glob  e g  a directory called logs that matches log   empty directories  i e  the result is 0  extremely large directories  listing them all could exhaust memory    Here s a solution that handles all of them   ls 2 gt  dev null -Ubad1 -- log    wc -l   Explanation    -U causes ls to not sort the entries  meaning it doesn t need to load the entire directory listing in memory -b prints C-style escapes for nongraphic characters  crucially causing newlines to be printed as  n  -a prints out all files  even hidden files  not strictly needed when the glob log  implies no hidden files  -d prints out directories without attempting to list the contents of the directory  which is what ls normally would do -1 makes sure that it s on one column  ls does this automatically when writing to a pipe  so it s not strictly necessary  2 gt  dev null redirects stderr so that if there are 0 log files  ignore the error message   Note that shopt -s nullglob would cause ls to list the entire working directory instead   wc -l consumes the directory listing as it s being generated  so the output of ls is never in memory at any point in time  -- File names are separated from the command using -- so as not to be understood as arguments to ls  in case log  is removed    The shell will expand log  to the full list of files  which may exhaust memory if it s a lot of files  so then running it through grep is be better   ls -Uba1   grep  log   wc -l   This last one handles extremely large directories of files without using a lot of memory  albeit it does use a subshell    The -d is no longer necessary  because it s only listing the contents of the current directory

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Here is a generic Bash function you can use in your scripts         see https   stackoverflow com a 11307382 430062     function countFiles           shopt -s nullglob         logfiles   1          echo    logfiles                FILES COUNT   countFiles  quot  file-  quot

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If you have a lot of files and you don t want to use the elegant shopt -s nullglob and bash array solution  you can use find and so on as long as you don t print out the file name  which might contain newlines    find -maxdepth 1 -name  log   -not -name      -printf   i n    wc -l   This will find all files that match log  and that don t start with        The  not name     is redunant  but it s important to note that the default for  ls  is to not show dot-files  but the default for find is to include them   This is a correct answer  and handles any type of file name you can throw at it  because the file name is never passed around between commands   But  the shopt nullglob answer is the best answer

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Here s what I always do      ls log    awk  END print NR

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You can use the -R option to find the files along with those inside the recursive directories  ls -R   wc -l    to find all the files  ls -R   grep log   wc -l    to find the files which contains the word log   you can use patterns on the grep

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Here is my one liner for this     file count    shopt -s nullglob   set --  directory to search inside     echo

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The accepted answer for this question is wrong  but I have low rep so can t add a comment to it   The correct answer to this question is given by Mat   shopt -s nullglob logfiles    log  echo    logfiles       The problem with the accepted answer is that wc -l counts the number of newline characters  and counts them even if they print to the terminal as     in the output of  ls -l   This means that the accepted answer FAILS when a filename contains a newline character  I have tested the suggested command   ls -l log    wc -l   and it erroneously reports a value of 2 even if there is only 1 file matching the pattern whose name happens to contain a newline character  For example   touch log   n def ls log  -l   wc -l

[bash] Is there a bash command which counts files?

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