/flags /find/find-print0-xargs-0

find -print0 | xargs -0: handle file names with spaces and newlines

updated 2026-10-24

tool: find
command: find
flag: -print0
default: off (-print ends each path with a newline)

find . -name '*.txt' -print0 | xargs -0 wc -l passes every file name to wc intact, even names with spaces, quotes or newlines. -print0 prints each path followed by a NUL byte instead of a newline, and xargs -0 (--null) splits its input on NUL bytes only and treats quotes and backslashes as ordinary characters. NUL is the only byte that cannot appear in a Unix file name, so the pair is always unambiguous.

Without and with -print0

bash

mkdir -p proj
touch proj/a.txt 'proj/my file.txt'
echo '-- newline separated'; find proj -name '*.txt' | xargs ls 2>&1 | sort
echo '-- NUL separated'; find proj -name '*.txt' -print0 | xargs -0 ls | sort
echo '-- NUL shown as |'; find proj -name '*.txt' -print0 | sort -z | tr '\0' '|'; echo

Output

-- newline separated
ls: cannot access 'file.txt': No such file or directory
ls: cannot access 'proj/my': No such file or directory
proj/a.txt
-- NUL separated
proj/a.txt
proj/my file.txt
-- NUL shown as |
proj/a.txt|proj/my file.txt|

Plain xargs splits proj/my file.txt into proj/my and file.txt, and ls fails on both. With -print0 and -0 the name arrives as one argument.

Characters that break the newline form

Name contains	find \| xargs	find -print0 \| xargs -0
space or tab	split into several arguments	one argument
single quote (don't.txt)	xargs: unmatched single quote	one argument
double quote or backslash	quote removed or error	one argument
newline	split into two names	one argument
leading dash (-x.txt)	safe with find . (names start with ./)	same: -0 does not change the name itself

The single-quote case is the xargs: unmatched single quote error.

Useful companions

Option	Tool	What it does
-0, --null	xargs	Input items end with NUL; quotes and backslashes are literal
-r, --no-run-if-empty	GNU xargs	Do not run the command if find printed nothing
-n N	xargs	At most N names per command invocation
-P N	GNU/BSD xargs	Run up to N commands in parallel
-z	GNU grep, sort	Read and write NUL-separated lines, so pipelines keep the NUL format
read -r -d ''	bash	Read one NUL-terminated name per loop iteration

bash

mkdir -p loop
touch 'loop/one two.txt' loop/three.txt
find loop -type f -print0 | sort -z | while IFS= read -r -d '' f; do printf '[%s]\n' "$f"; done

Output

[loop/one two.txt]
[loop/three.txt]

-print0 or -exec ... +

find ... -exec cmd {} + gives the same safety without a pipe and works with every POSIX find; see find -exec + vs ;. The pipe form is worth it when you need xargs features such as -P for parallel runs or -n to control batch size. Either way the command receives as many names per invocation as fit in the system limit, which avoids Argument list too long.

Pitfalls

-print0 must be the action: in find . -name a -o -name b -print0 it applies only to the second test. Group the tests: find . \( -name a -o -name b \) -print0.
Every program in the pipe must understand NUL: head, grep without -z, or xargs without -0 will mangle it.
On Git Bash, names still follow Windows rules (no : or *), but spaces are common, so the pair matters there too.

FAQ

Why does xargs say unmatched single quote?

Without -0, xargs splits on blanks and interprets quotes and backslashes, so a name such as don't.txt breaks it. Use find -print0 | xargs -0, which passes names unchanged.

Is -print0 portable?

GNU, BSD/macOS and BusyBox find all support it, and POSIX.1-2024 added find -print0 and xargs -0. Older strictly POSIX systems may lack it; find -exec cmd {} + works everywhere.

How do I read -print0 output in a bash loop?

Use while IFS= read -r -d '' f; do ...; done < <(find . -type f -print0). The empty -d '' makes read stop at each NUL byte.

Sources

errors · findxargs: unmatched single quote; by default quotes are special to xargs unless you use the -0 optionxargs: unmatched single quote happens when an input line has an apostrophe, like a file named it's.txt. Use find -print0 with xargs -0, or xargs -d on newlines.flags · findfind -exec {} + vs -exec {} \;: batch or one command per filefind -exec cmd {} + runs one command for many files; -exec cmd {} ';' runs one per file. Speed, exit status, where {} may go and missing argument errors.commands · findfind . -name "*.log": find files by name or extensionfind . -name '*.log' finds files by name below a directory; -iname ignores case, -type f limits to files. Why the pattern must be quoted, and acting on results.errors · coreutilsbash: /usr/bin/rm: Argument list too longArgument list too long (E2BIG) means a glob like rm *.log expanded to more arguments than the kernel accepts. Use find -delete, find -exec {} + or xargs.