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📄 NAME

printf - format and print data

🚀 Quick Reference

Use Case	Command	Description
Print formatted integer	printf '%d\n' 42	Outputs "42" with newline
Print string with escape sequences	printf 'Hello\nWorld'	Prints Hello and World on separate lines
Print Unicode character	printf '\u20AC\n'	Prints Euro currency symbol (€)
Print with precision	printf '%.2f\n' 3.14159	Outputs "3.14"

📖 SYNOPSIS

printf FORMAT [ARGUMENT]...

📝 DESCRIPTION

printf does formatted printing of text. It prints the FORMAT string, interpreting '%' directives and '\' escapes to format numeric and string arguments in a way that is mostly similar to the C printf function. (See printf format directives in libc manual for details.) The differences are listed below.

Due to shell aliases and built-in printf functions, using an unadorned printf interactively or in a script may get you different functionality. Invoke it via env (i.e., env printf ...) to avoid interference from the shell.

• 🔄 The FORMAT argument is reused as necessary to convert all the given ARGUMENTs. For example, printf %s a b outputs 'ab'.
• ❌ Missing ARGUMENTs are treated as null strings or as zeros, depending on context. For example, printf %sx%d prints 'x0'.
• ⏹️ An additional escape, \c, causes printf to produce no further output. For example, printf 'A%sC\cD%sF' B E prints 'ABC'.
• 🔢 The hexadecimal escape sequence \xHH has at most two digits, unlike C. For example, printf '\x07e' prints two bytes.
• 📝 An additional directive %b prints its argument string with \ escapes interpreted similarly to FORMAT, except octal escapes are \0OOO (0 to 3 octal digits). If a precision is given, it limits bytes printed.
• 💻 An additional directive %q prints its argument string in a format reusable by most shells, using POSIX $'...' syntax and quoting shell metacharacters. Equivalent to ls --quoting=shell-escape.
• 🔢 Numeric arguments must be single C constants, possibly with leading + or -. For example, printf %.4d -3 outputs '-0003'.
• 🔤 If the leading character of a numeric argument is " or ', its value is the numeric value of the following character. For example, printf "%d" "'a" outputs '97' on ASCII hosts.
• 🌐 A floating point argument is interpreted according to LC_NUMERIC and printed according to the current locale. For example, in a locale with comma as decimal point, printf '%g %g' 2,5 2.5 outputs '2,5 2,5'.

printf interprets \OOO in FORMAT as an octal number (1 to 3 digits) specifying a byte, and \xHH as hexadecimal. When \OOO specifies a number >255, the ninth bit is ignored. For example, printf '\400' is equivalent to printf '\0'.

🌟 printf interprets two character syntaxes from ISO C 99: \u for 16-bit Unicode (4 hex digits) and \U for 32-bit Unicode (8 hex digits). It outputs Unicode characters according to LC_CTYPE locale. Ranges U+0000…U+009F, U+D800…U+DFFF cannot be specified except for U+0024 ($), U+0040 (@), and U+0060 (`).

🛠️ Processing of \u and \U requires a full-featured iconv facility, activated on glibc 2.2+ or with libiconv installed. Otherwise, they print as-is.

Here is how to convert a piece of text into a shell script which will output this text in a locale-independent way:

$ LC_CTYPE=zh_CN.big5 /usr/local/bin/printf \
    '\u4e2d\u6587\n' > sample.txt
$ recode BIG5..JAVA < sample.txt \
    | sed -e "s|^|/usr/local/bin/printf '|" -e "s|$|\\\\n'|" \
    > sample.sh

⚙️ OPTIONS

The only options are a lone --help or --version. See Common options. Options must precede operands.

💡 Examples

🌍 Unicode Examples

For example, a string containing the Euro currency symbol:

$ env printf '\u20AC 14.95'

will be output correctly in all locales supporting the Euro symbol. Similarly, a Chinese string:

$ env printf '\u4e2d\u6587'

will be output correctly in all Chinese locales.

Note that these examples invoke printf via env to avoid shell aliases or built‑ins.

🚪 Exit Codes

An exit status of 0 indicates success, and a nonzero value indicates failure.

📄 NAME 🚀 Quick Reference 📖 SYNOPSIS 📝 DESCRIPTION ⚙️ OPTIONS 💡 Examples 🚪 Exit Codes