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{{Short description|Shell command for extracting printable text from a binary file}}

{{lowercase}}

{{distinguish|string (computing)}}

{{Oneone source |date=JulyApril 20082024}}

In [[computer software]], '''strings''' is a program in [[Unix-like]] [[operating system]]s that finds and prints text [[string (computer science)|strings]] embedded in [[binary files]] such as executables. It can be used on object files and [[core dump]]s.

{{Portal|FreeInfobox software}}

| name = strings

| logo =

| screenshot = Strings Command.png

| screenshot size =

| caption = The {{code|strings}} command

| author =

| developer =

| released =

| latest release version =

| latest release date =

| programming language = [[C (programming language)|C]]

| operating system = [[Unix]], [[Unix-like]], [[Plan 9 from Bell Labs|Plan 9]], [[Inferno (operating system)|Inferno]]

| platform = [[Cross-platform]]

| genre = [[Command (computing)|Command]]

| license = Plan 9: [[MIT License]]

| website =

}}

<code>'''strings'''</code> is a [[Shell (computing)|shell command]] that extracts [[printable character]] [[String (computer science)|strings]] from a [[computer file|file]] {{endash}} which is particular useful for analyzing the content of a [[binary file]]. By definition, a binary file contains data that is not printable text yet a binary file often does contain some printable character text {{endash}} often in relatively short sequences distributed throughout the file. These portions of the binary file can be informative as to what the file contains overall. For a [[text file]], a file containing all printable characters, the command prints the entire file content, and therefore, provides no utility over more commonly used file output commands such as <code>[[cat (Unix)|cat]]</code>.

<code>Strings</code>The arecommand recognized by lookingsearches for sequences of at least 4 (by default) printable characters terminatingthat inend with a NUL character (that is, [[null-terminated string|NUL character]]s) but ignores any sequence that is less than a specified length or 4 characters by default. Some implementations provide options for determining what is recognized as a printable character, which is useful for finding non-[[ASCII]] and [[wide character]] text. By default, it only selects strings from the initialized and loaded sections of an object file. For other types of files, it selects strings from the whole file.

The command is available in [[Unix]], [[Plan 9 from Bell Labs|Plan 9]], [[Inferno (operating system)|Inferno]], and [[Unix-like]] systems. It is part of the [[GNU Binary Utilities]] ({{mono|binutils}}), and has been portedimplemented toin other operating systems including [[Microsoft Windows|Windows]].<ref>[[cygwin]]</ref>

Common usage includes piping its output to [[grep|<code>grep</code>]] and <tt>[[Fold (Unix)|fold]]</tt> or redirecting the output to a [[Computer file|<code>file</code>]].<ref>{{cite book|last=Kiddle|first=Oliver |author2=Jerry Peek |author3=Peter Stephenson|title=From Bash to Z Shell |year=2005 |___location=New York, NY |publisher=Apress|isbn=978-1-590-59376-9|page=413 |oclc=57450917 |url=http://www.apress.com/9781590593769}}</ref>

It is part of the [[GNU Binary Utilities]] (binutils), and has been ported to other operating systems including [[Microsoft Windows]].<ref>[[cygwin]]</ref>

==Example==

Using <code>strings</code> to print sequences of characters that are at least 8 characters long (this command prints the system's [[BIOS]] information; should be run as root):

<source lang="bash">

dd if=/dev/mem bs=1k skip=768 count=256 2>/dev/null | strings -n 8 | less

</source>

The following command searches the system's [[BIOS]] for strings that are at 8 characters long:

==See also==

{{Portal|Free software}}

dd if=/dev/mem bs=1k skip=768 count=256 2>[[/dev/null]] | strings -n 8 | less

*<tt>[[Cat (Unix)|cat]]</tt>

*[[Paste (Unix)|paste]]

==See also==

*[[GNU Debugger]]

{{Portal|Free and open-source software}}

*<tt>[[Strip (Unix)|strip]]</tt>

* {{Annotated link|GNU Debugger}}

* {{Annotated link|List of POSIX commands}}

* {{Annotated link|Paste (Unix)}}

* {{Annotated link|Strip (Unix)}}

==References==

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==External links==

{{Wikibooks|Guide to Unix|Commands}}

{{One source|date=July 2008}}

* {{man|cu|strings|SUS}}

* {{man|1|strings|Plan 9}}

* {{man|1|strings|Inferno}}

{{unixUnix commands}}

{{Plan 9 commands}}

[[Category:Unix text processing utilities]]

[[Category:Unix SUS2008 utilities]]

[[Category:Plan 9 commands]]

[[Category:Inferno (operating system) commands]]

[[Category:String (computer science)]]

{{unix-stub}}