printf (Unix)

{{short description|Standard UNIX utility}}

{{lowercase|title=printf}}

{{Refimprove|date=July 2010}}

{{Infobox software

| name = printf

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| screenshot = Printf-example-command.gif

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| developer = Various open-source and commercial developers

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| operating system = Unix and Unix-like

| platform = Cross-platform

| genre = Command

| license = coreutils: GPLv3+{{Cite web|url=https://linux.die.net/man/1/printf|title=printf(1): format/print data - Linux man page|website=linux.die.net}}

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In Unix and Unix-like operating systems, printf is a shell builtin (and utility program{{Cite web|url=https://www.gnu.org/software/coreutils/manual/coreutils.html#printf-invocation|title=GNU Coreutils|website=www.gnu.org}}) that formats and outputs text like the same-named C function.

Originally named for outputting to a printer, it actually outputs to standard output.{{man|1|printf|Linux}}

The command accepts a format string, which specifies how to format values, and a list of values.

Characters in the format string are copied to the output verbatim except when a format specifier is found which causes a value to be output.

In addition to the standard format specifiers, %b causes the command to expand backslash escape sequences (for example \n for newline), and %q outputs an item that can be used as shell input. The format string is reused if there are more items than format specs. Unused format specs provide a zero value or null string.