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I have massive of files in my system and every file has one corresponded file name. For example,

test.pdf has a test2.pdf has a

test.pdf and test2.pdf are the original files and and are generated by my script.

I need to find out if all of my original files have the 'filename' corresponded to the original file.

I can use

find /project/ -name "*.pdf" | wc -l
find /project/ -name "*" | wc -l

to find out if the numbers match but I need to know which file has no corresponded file.

Can anyone help me about it? Thanks a lot!

share|improve this question
Is it a single folder /project/, or are subdirectories involved? – Daniel Beck May 24 '13 at 19:13
subdirectories included.. – FlyingCat May 24 '13 at 19:15
is test.pdf and (and so on) always in the same directory? – evilsoup May 24 '13 at 19:20
yes they are all in the same dir – FlyingCat May 24 '13 at 19:21

2 Answers 2

Quicky script, adapt as you see fit:

#!/usr/bin/env bash

find /project/ -name '*.pdf' -print0 | while read -d $'\0' i; do
  if [ ! -e "${i/%.pdf/}" ]; then
    echo "${i/%.pdf/} doesn't exist!"

exit 0

-d $'\0' sets the delimiter for read to nullbyte, while -print0 is the equivalent for find, so this should be bulletproof against files with spaces and newlines in their names (obviously irrelevant in this case, but useful to know in general). ${i/%.pdf/} replaces the .pdf at the end of the variable $i with Other than that, this is all standard shell scripting stuff.

If you wanted to shorten it even more, you could also use

[ -e "${i/%.pdf/}" ] || echo "${i/%.pdf/} doesn't exist!"

...instead of the if statement. I think that if is easier to work with if you're using more than a single, short line (you can get around this by using a function, but at that point you aren't getting any psace saving vs. using the if).

Assuming you have bash 4+ (you probably do; you can check with bash --version), you can use the globstar option instead of find:

#!/usr/bin/env bash

shopt -s globstar
for f in /project/**/*.pdf; do
  if [ ! -e "${f/%.pdf/}" ]; then
    echo "${f/%.pdf/} doesn't exist!"

exit 0

This has the advantage of being pure bash, so it should be faster (only noticeably so with at least hundreds of files, though).

share|improve this answer
You guard against newlines, but the [ ... ] test would still break if $i had spaces. – grawity May 24 '13 at 19:58
@grawity - I can't believe I forgot to quote the variable, fixed. – evilsoup May 24 '13 at 20:00
+1 for '-d '\0'... but do you need /bin/env bash? /bin/bash is a POSIX necessity. Do you really worry about which bash you hit? – Rich Homolka May 24 '13 at 20:07
@RichHomolka AFAIK there's no actual downside to using /usr/bin/env, and while it may not be necessary in this case, I look at it as a good habit to form for working with other laguages. – evilsoup May 24 '13 at 20:10
@RichHomolka: /bin/sh is a POSIX necessity. bash, on the other hand, is a third-party program, and it's frequently in /usr/bin, /usr/local/bin, or even /usr/pkg/bin. – grawity May 24 '13 at 20:19

Here are two ways you could do it. One is a godawful Bash one-liner which spawns at least one, possibly two, processes for each file it matches:

[me@box] $ for file in `find -name '*.pdf' -exec perl -le'$f=shift(); $f =~ s@\.pdf$@@; print $f' {} \;`; do (TESTFILE="$"; if [ ! -f $TESTFILE ]; then echo "missing $TESTFILE"; fi); done

Since that's enough to make anyone's eyes bleed, here's a Perl script which does the same job, much more sanely than any Bash script ever could:

#!/usr/bin/env perl
use strict;

my $path = shift() || die "$0 requires a path argument\n";
my @files = `find "$path" -name '*.pdf'`;

foreach my $file (@files) {
  chomp $file;
  my $zip = $file;
  $zip =~ s@\.pdf$;
  next if -f $zip;
  print "missing $zip\n";

Copy that into, e.g., '', then invoke /project/.

share|improve this answer
for file in `find … is a common anti-pattern and should be avoided. See: – slhck May 25 '13 at 9:50

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