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div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">This article is about function declarations. For the prototype property of JavaScript functions and objects, see <a href="/wiki/JavaScript#Object-orientation_(prototype-based)" title="JavaScript">JavaScript § Object-orientation (prototype-based)</a>. For other uses, see <a href="/wiki/Software_prototyping" title="Software prototyping">Software prototyping</a>.</div> <style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-More_citations_needed plainlinks metadata ambox ambox-content ambox-Refimprove" role="presentation"><tbody><tr><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Function_prototype" title="Special:EditPage/Function prototype">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Function+prototype%22">"Function prototype"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Function+prototype%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Function+prototype%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Function+prototype%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Function+prototype%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Function+prototype%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">September 2016</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p>In <a href="/wiki/Computer_programming" title="Computer programming">computer programming</a>, a <b>function prototype</b> is a <a href="/wiki/Declaration_(computer_programming)" title="Declaration (computer programming)">declaration</a> of a <a href="/wiki/Function_(programming)" class="mw-redirect" title="Function (programming)">function</a> that specifies the function's name and <a href="/wiki/Type_signature" title="Type signature">type signature</a> (<a href="/wiki/Arity" title="Arity">arity</a>, <a href="/wiki/Data_type" title="Data type">data types</a> of <a href="/wiki/Parameter_(computer_programming)" title="Parameter (computer programming)">parameters</a>, and <a href="/wiki/Return_type" title="Return type">return type</a>), but omits the function body. While a function definition specifies <i>how</i> the function does what it does (the "implementation"), a function prototype merely specifies its interface, i.e. <i>what</i> data types go in and come out of it. The term "function prototype" is particularly used in the context of the programming languages <a href="/wiki/C_(programming_language)" title="C (programming language)">C</a> and <a href="/wiki/C%2B%2B" title="C++">C++</a> where placing <a href="/wiki/Forward_declaration" title="Forward declaration">forward declarations</a> of functions in <a href="/wiki/Header_file" class="mw-redirect" title="Header file">header files</a> allows for splitting a program into <a href="/wiki/Translation_unit_(programming)" title="Translation unit (programming)">translation units</a>, i.e. into parts that a <a href="/wiki/Compiler" title="Compiler">compiler</a> can separately translate into <a href="/wiki/Object_file" title="Object file">object files</a>, to be combined by a <a href="/wiki/Linker_(computing)" title="Linker (computing)">linker</a> into an <a href="/wiki/Executable" title="Executable">executable</a> or a <a href="/wiki/Library_(computing)" title="Library (computing)">library</a>. The function declaration precedes the function definition, giving details of name, return type, and storage class along with other relevant attributes.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>Function prototypes can be used when either:<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p> <ul><li>Defining an ExternalType</li> <li>Creating an Interface part</li></ul> <p>In a prototype, parameter names are optional (and in C/C++ have function prototype <a href="/wiki/Scope_(computer_science)" title="Scope (computer science)">scope</a>, meaning their scope ends at the end of the prototype), however, the type is necessary along with all modifiers (e.g. if it is a <a href="/wiki/Pointer_(computer_programming)" title="Pointer (computer programming)">pointer</a> or a reference to <style data-mw-deduplicate="TemplateStyles:r886049734">.mw-parser-output .monospaced{font-family:monospace,monospace}</style><span class="monospaced"><a href="/wiki/Const" class="mw-redirect" title="Const">const</a></span> parameter) except <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">const</span> alone. </p><p>In <a href="/wiki/Object-oriented_programming" title="Object-oriented programming">object-oriented programming</a>, <a href="/wiki/Protocol_(object-oriented_programming)" class="mw-redirect" title="Protocol (object-oriented programming)">interfaces</a> and <a href="/wiki/Method_(computer_programming)#Abstract_methods" title="Method (computer programming)">abstract methods</a> serve much the same purpose. </p> <div id="toc" class="toc" role="navigation" aria-labelledby="mw-toc-heading"><input type="checkbox" role="button" id="toctogglecheckbox" class="toctogglecheckbox" style="display:none"><div class="toctitle" lang="en" dir="ltr"><h2 id="mw-toc-heading">Contents</h2><span class="toctogglespan"><label class="toctogglelabel" for="toctogglecheckbox"></label></span></div> <ul> <li class="toclevel-1 tocsection-1"><a href="#Example"><span class="tocnumber">1</span> <span class="toctext">Example</span></a></li> <li class="toclevel-1 tocsection-2"><a href="#Uses"><span class="tocnumber">2</span> <span class="toctext">Uses</span></a> <ul> <li class="toclevel-2 tocsection-3"><a href="#Creating_library_interfaces"><span class="tocnumber">2.1</span> <span class="toctext">Creating library interfaces</span></a></li> <li class="toclevel-2 tocsection-4"><a href="#Class_declaration"><span class="tocnumber">2.2</span> <span class="toctext">Class declaration</span></a></li> </ul> </li> <li class="toclevel-1 tocsection-5"><a href="#See_also"><span class="tocnumber">3</span> <span class="toctext">See also</span></a></li> <li class="toclevel-1 tocsection-6"><a href="#References"><span class="tocnumber">4</span> <span class="toctext">References</span></a></li> </ul> </div> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(1)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="Example">Example</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Function_prototype&action=edit&section=1" title="Edit section: Example" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-1 collapsible-block" id="mf-section-1"> <p>Consider the following function prototype: </p> <div class="mw-highlight mw-highlight-lang-c mw-content-ltr" dir="ltr"><pre><span></span><span class="kt">void</span><span class="w"> </span><span class="nf">sum</span><span class="p">(</span><span class="kt">int</span><span class="w"> </span><span class="n">a</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">b</span><span class="p">);</span> </pre></div> <p>or </p> <div class="mw-highlight mw-highlight-lang-c mw-content-ltr" dir="ltr"><pre><span></span><span class="kt">void</span><span class="w"> </span><span class="nf">sum</span><span class="p">(</span><span class="kt">int</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="p">);</span> </pre></div> <p>or </p> <div class="mw-highlight mw-highlight-lang-cpp mw-content-ltr" dir="ltr"><pre><span></span><span class="k">auto</span><span class="w"> </span><span class="n">sum</span><span class="p">(</span><span class="kt">int</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="p">)</span><span class="w"> </span><span class="o">-></span><span class="w"> </span><span class="kt">void</span><span class="p">;</span><span class="w"> </span><span class="c1">// C++ only</span> </pre></div> <p>Function prototypes include the function signature, the name of the function, return type and access specifier. In this case the name of the function is "Sum". The function signature defines the number of parameters and their types. The return type is "void". This means that the function is not going to return any value. Note that the parameter names in the first example are optional. </p> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(2)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="Uses">Uses</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Function_prototype&action=edit&section=2" title="Edit section: Uses" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-2 collapsible-block" id="mf-section-2"> <p>In early versions of C, if a function was not previously declared and its name occurred in an expression followed by a left parenthesis, it was implicitly declared as a function that returns an <code>int</code> and nothing was assumed about its arguments. In this case the compiler would not be able to perform compile-time validity checking of the number and type(s) of arguments. The <a href="/wiki/C99" title="C99">C99</a> standard requires the use of prototypes. </p> <div class="mw-highlight mw-highlight-lang-c mw-content-ltr" dir="ltr"><pre><span></span><span class="kt">char</span><span class="w"> </span><span class="nf">MyFunction</span><span class="p">(</span><span class="kt">int</span><span class="w"> </span><span class="n">a</span><span class="p">);</span><span class="w"> </span><span class="cm">/* Function prototype */</span> <span class="cp">#include</span><span class="w"> </span><span class="cpf"><stdio.h></span> <span class="cp">#include</span><span class="w"> </span><span class="cpf"><limits.h></span><span class="c1"> </span> <span class="kt">int</span><span class="w"> </span><span class="nf">main</span><span class="p">(</span><span class="kt">void</span><span class="p">)</span><span class="w"> </span> <span class="p">{</span> <span class="w"> </span><span class="n">putchar</span><span class="p">(</span><span class="n">MyFunction</span><span class="p">(</span><span class="mi">-1</span><span class="p">));</span><span class="w"> </span><span class="cm">/* Correctly formatted call */</span> <span class="w"> </span><span class="n">putchar</span><span class="p">(</span><span class="n">MyFunction</span><span class="p">(</span><span class="mf">1.5</span><span class="p">));</span><span class="w"> </span><span class="cm">/* Compiler generates a warning because of type mismatch */</span> <span class="w"> </span><span class="n">putchar</span><span class="p">(</span><span class="n">MyFunction</span><span class="p">(</span><span class="s">"IncorrectArgType"</span><span class="p">));</span><span class="w"> </span><span class="cm">/* Compiler will generate a warning */</span> <span class="w"> </span><span class="n">putchar</span><span class="p">(</span><span class="n">MyFunction</span><span class="p">());</span><span class="w"> </span><span class="cm">/* Compiler will generate an Error too few arguments */</span> <span class="w"> </span> <span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">one</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">1</span><span class="p">;</span> <span class="w"> </span><span class="n">putchar</span><span class="p">(</span><span class="n">MyFunction</span><span class="p">(</span><span class="n">INT_MAX</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="n">one</span><span class="p">));</span><span class="w"> </span><span class="cm">/* Although adding 1 to the maximum integer </span> <span class="cm"> /* is an error it cannot be detected at compile time */</span> <span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span> <span class="p">}</span> <span class="kt">char</span><span class="w"> </span><span class="nf">MyFunction</span><span class="p">(</span><span class="kt">int</span><span class="w"> </span><span class="n">n</span><span class="p">)</span><span class="w"> </span><span class="cm">/* Function definition */</span> <span class="p">{</span> <span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">n</span><span class="w"> </span><span class="o">></span><span class="w"> </span><span class="mi">0</span><span class="p">)</span><span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="sc">'>'</span><span class="p">;</span> <span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">n</span><span class="w"> </span><span class="o"><</span><span class="w"> </span><span class="mi">0</span><span class="p">)</span><span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="sc">'<'</span><span class="p">;</span><span class="w"> </span> <span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="sc">'='</span><span class="p">;</span> <span class="p">}</span> </pre></div> <p>The function <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">MyFunction</span> expects to be called with an integer argument. By including the function prototype, you inform the compiler that the function takes one integer argument and you enable the compiler to catch incorrectly specified calls. </p> <div class="mw-heading mw-heading3"><h3 id="Creating_library_interfaces">Creating library interfaces</h3><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Function_prototype&action=edit&section=3" title="Edit section: Creating library interfaces" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div> <p>By placing function prototypes in a <a href="/wiki/Include_directive" title="Include directive">header file</a>, one can specify an <a href="/wiki/Protocol_(object-oriented_programming)" class="mw-redirect" title="Protocol (object-oriented programming)">interface</a> for a <a href="/wiki/Library_(computing)" title="Library (computing)">library</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Class_declaration">Class declaration</h3><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Function_prototype&action=edit&section=4" title="Edit section: Class declaration" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div> <p>In C++, function prototypes are also used in <a href="/wiki/Class_(computer_science)" class="mw-redirect" title="Class (computer science)">class</a> definitions. </p> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(3)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="See_also">See also</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Function_prototype&action=edit&section=5" title="Edit section: See also" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-3 collapsible-block" id="mf-section-3"> <ul><li><a href="/wiki/Modular_programming" title="Modular programming">Modular programming</a></li> <li><a href="/wiki/Protocol_(object-oriented_programming)" class="mw-redirect" title="Protocol (object-oriented programming)">Protocol (object-oriented programming)</a></li> <li><a href="/wiki/Method_(computer_programming)#Abstract_methods" title="Method (computer programming)">Abstract method</a></li></ul> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(4)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="References">References</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Function_prototype&action=edit&section=6" title="Edit section: References" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-4 collapsible-block" id="mf-section-4"> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFTylerMSFT2023" class="citation web cs1">TylerMSFT (2023-01-25). <a rel="nofollow" class="external text" href="https://learn.microsoft.com/en-us/cpp/c-language/function-prototypes?view=msvc-170">"Function Prototypes"</a>. <i>learn.microsoft.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-08-09</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=learn.microsoft.com&rft.atitle=Function+Prototypes&rft.date=2023-01-25&rft.au=TylerMSFT&rft_id=https%3A%2F%2Flearn.microsoft.com%2Fen-us%2Fcpp%2Fc-language%2Ffunction-prototypes%3Fview%3Dmsvc-170&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFunction+prototype" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.ibm.com/docs/es/rbd/9.1.1.2?topic=functions-function-prototypes">"Function prototypes"</a>. <i>www.ibm.com</i>. 2018-10-25<span class="reference-accessdate">. Retrieved <span class="nowrap">2023-08-09</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.ibm.com&rft.atitle=Function+prototypes&rft.date=2018-10-25&rft_id=https%3A%2F%2Fwww.ibm.com%2Fdocs%2Fes%2Frbd%2F9.1.1.2%3Ftopic%3Dfunctions-function-prototypes&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFunction+prototype" class="Z3988"></span></span> </li> </ol></div></div> <style data-mw-deduplicate="TemplateStyles:r1239549316">.mw-parser-output .refbegin{margin-bottom:0.5em}.mw-parser-output .refbegin-hanging-indents>ul{margin-left:0}.mw-parser-output .refbegin-hanging-indents>ul>li{margin-left:0;padding-left:3.2em;text-indent:-3.2em}.mw-parser-output .refbegin-hanging-indents ul,.mw-parser-output .refbegin-hanging-indents ul li{list-style:none}@media(max-width:720px){.mw-parser-output .refbegin-hanging-indents>ul>li{padding-left:1.6em;text-indent:-1.6em}}.mw-parser-output .refbegin-columns{margin-top:0.3em}.mw-parser-output .refbegin-columns ul{margin-top:0}.mw-parser-output .refbegin-columns li{page-break-inside:avoid;break-inside:avoid-column}@media screen{.mw-parser-output .refbegin{font-size:90%}}</style><div class="refbegin" style=""> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKernighanRitchie_Afree1988" class="citation book cs1"><a href="/wiki/Brian_Kernighan" title="Brian Kernighan">Kernighan, Brian W.</a>; <a href="/wiki/Dennis_Ritchie" title="Dennis Ritchie">Ritchie Afree, Dennis M.</a> (1988). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/cprogramminglang00bria"><i>The C Programming Language</i></a></span> (2nd ed.). Upper Saddle River, NJ: Prentice Hall PTR. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-13-110362-8" title="Special:BookSources/0-13-110362-8"><bdi>0-13-110362-8</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+C+Programming+Language&rft.place=Upper+Saddle+River%2C+NJ&rft.edition=2nd&rft.pub=Prentice+Hall+PTR&rft.date=1988&rft.isbn=0-13-110362-8&rft.aulast=Kernighan&rft.aufirst=Brian+W.&rft.au=Ritchie+Afree%2C+Dennis+M.&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fcprogramminglang00bria&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFunction+prototype" class="Z3988"></span></li></ul> </div>    </section></div> <noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?useformat=mobile&type=1x1&usesul3=0" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" 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