{"id":2008,"date":"2024-03-12T09:04:09","date_gmt":"2024-03-12T09:04:09","guid":{"rendered":"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/"},"modified":"2024-03-25T14:33:46","modified_gmt":"2024-03-25T14:33:46","slug":"what-is-the-usage-of-fopen-in-the-c-language","status":"publish","type":"post","link":"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/","title":{"rendered":"What is the usage of fopen in the C language?"},"content":{"rendered":"<p>In C language, the fopen function is used to open a file and returns a file pointer pointing to that file. The prototype of the fopen function is as follows:<\/p>\n<pre class=\"post-pre\"><code>FILE *<span class=\"hljs-title function_\">fopen<\/span><span class=\"hljs-params\">(<span class=\"hljs-type\">const<\/span> <span class=\"hljs-type\">char<\/span> *filename, <span class=\"hljs-type\">const<\/span> <span class=\"hljs-type\">char<\/span> *mode)<\/span>;\r\n<\/code><\/pre>\n<p>In this case, filename refers to the path and name of the file to be opened, while mode represents the opening mode of the file. Some commonly used file opening modes include:<\/p>\n<ol>\n<li>&#8220;r&#8221;: Read-only mode, the file must exist, and if it does not, it will return <a href=\"https:\/\/www.prepbytes.com\/blog\/c-programming\/null-character-in-c\/#:~:text=The%20Null%20Character%20in%20C%20is%20represented%20using%20the%20escape,Character%20to%20mark%20its%20end%2e\">NULL<\/a>.<\/li>\n<li>&#8220;w&#8221; mode: Writing mode, create a new file if it does not exist, or truncate the file to 0 bytes if it already exists.<\/li>\n<li>Option:<br \/>\n&#8220;Option A: Append mode, create a new file if it does not exist, and writing will start from the end of the file.&#8221;<\/li>\n<li>&#8220;r+&#8221;: This mode allows reading and writing in a file that must already exist.<\/li>\n<li>&#8220;w+&#8221; mode: Read and write mode, creates a new file if it doesn&#8217;t exist, truncates the file to 0 bytes if it does exist.<\/li>\n<li>&#8220;mode a+&#8221; allows for reading and writing, creates a new file if it doesn&#8217;t exist, and starts writing from the end of the file.<\/li>\n<\/ol>\n<p>This is an example code:<\/p>\n<pre class=\"post-pre\"><code><span class=\"hljs-meta\">#<span class=\"hljs-keyword\">include<\/span> <span class=\"hljs-string\">&lt;stdio.h&gt;<\/span><\/span>\r\n\r\n<span class=\"hljs-type\">int<\/span> <span class=\"hljs-title function_\">main<\/span><span class=\"hljs-params\">()<\/span> {\r\n    FILE *file = fopen(<span class=\"hljs-string\">\"example.txt\"<\/span>, <span class=\"hljs-string\">\"w\"<\/span>);\r\n    <span class=\"hljs-keyword\">if<\/span> (file == <span class=\"hljs-literal\">NULL<\/span>) {\r\n        <span class=\"hljs-built_in\">printf<\/span>(<span class=\"hljs-string\">\"File open error\\n\"<\/span>);\r\n        <span class=\"hljs-keyword\">return<\/span> <span class=\"hljs-number\">1<\/span>;\r\n    }\r\n    \r\n    <span class=\"hljs-built_in\">fprintf<\/span>(file, <span class=\"hljs-string\">\"Hello, World!\"<\/span>);\r\n    \r\n    fclose(file);\r\n    \r\n    <span class=\"hljs-keyword\">return<\/span> <span class=\"hljs-number\">0<\/span>;\r\n}\r\n<\/code><\/pre>\n<p>In the code sample above, a file named example.txt was opened using write mode &#8220;w&#8221;, &#8220;Hello, World!&#8221; was written to the file, and then the file was closed.<\/p>\n<p>&nbsp;<\/p>\n<p>More tutorials<\/p>\n<p><a class=\"LinkSuggestion__Link-sc-1gewdgc-4 cLBplk\" href=\"https:\/\/www.silicloud.com\/blog\/reading-and-writing-data-using-python\/\" target=\"_blank\" rel=\"noopener\">Reading and Writing data using Python<span class=\"sc-gswNZR eASTkv\">(Opens in a new browser tab)<\/span><\/a><\/p>\n<p><a class=\"LinkSuggestion__Link-sc-1gewdgc-4 cLBplk\" href=\"https:\/\/www.silicloud.com\/blog\/what-is-the-difference-between-fread-and-fwrite-in-c-language\/\" target=\"_blank\" rel=\"noopener\">What is the difference between fread and fwrite in C language?<span class=\"sc-gswNZR eASTkv\">(Opens in a new browser tab)<\/span><\/a><\/p>\n<p><a class=\"LinkSuggestion__Link-sc-1gewdgc-4 cLBplk\" href=\"https:\/\/www.silicloud.com\/blog\/converting-a-string-to-a-byte-array-and-a-byte-array-to-a-string-in-the-java-programming-language\/\" target=\"_blank\" rel=\"noopener\">Converting string to array in the Java programming language<span class=\"sc-gswNZR eASTkv\">(Opens in a new browser tab)<\/span><\/a><\/p>\n<p><a class=\"LinkSuggestion__Link-sc-1gewdgc-4 cLBplk\" href=\"https:\/\/www.silicloud.com\/blog\/partition-in-linux\/\" target=\"_blank\" rel=\"noopener\">Partition in Linux Step-by-Step Guide<span class=\"sc-gswNZR eASTkv\">(Opens in a new browser tab)<\/span><\/a><\/p>\n<p><a class=\"LinkSuggestion__Link-sc-1gewdgc-4 cLBplk\" href=\"https:\/\/www.silicloud.com\/blog\/partition-in-linux\/\" target=\"_blank\" rel=\"noopener\">Partition in Linux Step-by-Step Guide<span class=\"sc-gswNZR eASTkv\">(Opens in a new browser tab)<\/span><\/a><\/p>\n<p><a class=\"LinkSuggestion__Link-sc-1gewdgc-4 cLBplk\" href=\"https:\/\/www.silicloud.com\/blog\/convert-string-to-character-in-java\/\" target=\"_blank\" rel=\"noopener\">convert string to character array in Java.<span class=\"sc-gswNZR eASTkv\">(Opens in a new browser tab)<\/span><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>In C language, the fopen function is used to open a file and returns a file pointer pointing to that file. The prototype of the fopen function is as follows: FILE *fopen(const char *filename, const char *mode); In this case, filename refers to the path and name of the file to be opened, while mode [&hellip;]<\/p>\n","protected":false},"author":8,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_import_markdown_pro_load_document_selector":0,"_import_markdown_pro_submit_text_textarea":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-2008","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v21.5 (Yoast SEO v21.5) - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>What is the usage of fopen in the C language? - Blog - Silicon Cloud<\/title>\n<meta name=\"description\" content=\"In C language, the fopen function is used to open a file and returns a file pointer pointing to that file. The prototype of the fopen function is as\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"What is the usage of fopen in the C language?\" \/>\n<meta property=\"og:description\" content=\"In C language, the fopen function is used to open a file and returns a file pointer pointing to that file. The prototype of the fopen function is as\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/\" \/>\n<meta property=\"og:site_name\" content=\"Blog - Silicon Cloud\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/SiliCloudGlobal\/\" \/>\n<meta property=\"article:published_time\" content=\"2024-03-12T09:04:09+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2024-03-25T14:33:46+00:00\" \/>\n<meta name=\"author\" content=\"William Carter\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@SiliCloudGlobal\" \/>\n<meta name=\"twitter:site\" content=\"@SiliCloudGlobal\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"William Carter\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/#article\",\"isPartOf\":{\"@id\":\"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/\"},\"author\":{\"name\":\"William Carter\",\"@id\":\"https:\/\/www.silicloud.com\/blog\/#\/schema\/person\/f697031891aacefc4b681d139781d3c0\"},\"headline\":\"What is the usage of fopen in the C language?\",\"datePublished\":\"2024-03-12T09:04:09+00:00\",\"dateModified\":\"2024-03-25T14:33:46+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/\"},\"wordCount\":314,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\/\/www.silicloud.com\/blog\/#organization\"},\"inLanguage\":\"en-US\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/\",\"url\":\"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/\",\"name\":\"What is the usage of fopen in the C language? - Blog - Silicon Cloud\",\"isPartOf\":{\"@id\":\"https:\/\/www.silicloud.com\/blog\/#website\"},\"datePublished\":\"2024-03-12T09:04:09+00:00\",\"dateModified\":\"2024-03-25T14:33:46+00:00\",\"description\":\"In C language, the fopen function is used to open a file and returns a file pointer pointing to that file. The prototype of the fopen function is as\",\"breadcrumb\":{\"@id\":\"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.silicloud.com\/blog\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"What is the usage of fopen in the C language?\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.silicloud.com\/blog\/#website\",\"url\":\"https:\/\/www.silicloud.com\/blog\/\",\"name\":\"Silicon Cloud Blog\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\/\/www.silicloud.com\/blog\/#organization\"},\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\/\/www.silicloud.com\/blog\/#organization\",\"name\":\"Silicon Cloud Blog\",\"url\":\"https:\/\/www.silicloud.com\/blog\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.silicloud.com\/blog\/#\/schema\/logo\/image\/\",\"url\":\"https:\/\/www.silicloud.com\/blog\/wp-content\/uploads\/2023\/11\/EN-SILICON-Full.png\",\"contentUrl\":\"https:\/\/www.silicloud.com\/blog\/wp-content\/uploads\/2023\/11\/EN-SILICON-Full.png\",\"width\":1024,\"height\":1024,\"caption\":\"Silicon Cloud Blog\"},\"image\":{\"@id\":\"https:\/\/www.silicloud.com\/blog\/#\/schema\/logo\/image\/\"},\"sameAs\":[\"https:\/\/www.facebook.com\/SiliCloudGlobal\/\",\"https:\/\/twitter.com\/SiliCloudGlobal\"]},{\"@type\":\"Person\",\"@id\":\"https:\/\/www.silicloud.com\/blog\/#\/schema\/person\/f697031891aacefc4b681d139781d3c0\",\"name\":\"William Carter\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.silicloud.com\/blog\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/1786698071dd8d74bec894b512f9e3c610c3a2a32985f67e688976cee3c8bbef?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/1786698071dd8d74bec894b512f9e3c610c3a2a32985f67e688976cee3c8bbef?s=96&d=mm&r=g\",\"caption\":\"William Carter\"},\"url\":\"https:\/\/www.silicloud.com\/blog\/author\/williamcarter\/\"}]}<\/script>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"What is the usage of fopen in the C language? - Blog - Silicon Cloud","description":"In C language, the fopen function is used to open a file and returns a file pointer pointing to that file. The prototype of the fopen function is as","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/","og_locale":"en_US","og_type":"article","og_title":"What is the usage of fopen in the C language?","og_description":"In C language, the fopen function is used to open a file and returns a file pointer pointing to that file. The prototype of the fopen function is as","og_url":"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/","og_site_name":"Blog - Silicon Cloud","article_publisher":"https:\/\/www.facebook.com\/SiliCloudGlobal\/","article_published_time":"2024-03-12T09:04:09+00:00","article_modified_time":"2024-03-25T14:33:46+00:00","author":"William Carter","twitter_card":"summary_large_image","twitter_creator":"@SiliCloudGlobal","twitter_site":"@SiliCloudGlobal","twitter_misc":{"Written by":"William Carter","Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/#article","isPartOf":{"@id":"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/"},"author":{"name":"William Carter","@id":"https:\/\/www.silicloud.com\/blog\/#\/schema\/person\/f697031891aacefc4b681d139781d3c0"},"headline":"What is the usage of fopen in the C language?","datePublished":"2024-03-12T09:04:09+00:00","dateModified":"2024-03-25T14:33:46+00:00","mainEntityOfPage":{"@id":"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/"},"wordCount":314,"commentCount":0,"publisher":{"@id":"https:\/\/www.silicloud.com\/blog\/#organization"},"inLanguage":"en-US"},{"@type":"WebPage","@id":"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/","url":"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/","name":"What is the usage of fopen in the C language? - Blog - Silicon Cloud","isPartOf":{"@id":"https:\/\/www.silicloud.com\/blog\/#website"},"datePublished":"2024-03-12T09:04:09+00:00","dateModified":"2024-03-25T14:33:46+00:00","description":"In C language, the fopen function is used to open a file and returns a file pointer pointing to that file. The prototype of the fopen function is as","breadcrumb":{"@id":"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/www.silicloud.com\/blog\/what-is-the-usage-of-fopen-in-the-c-language\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.silicloud.com\/blog\/"},{"@type":"ListItem","position":2,"name":"What is the usage of fopen in the C language?"}]},{"@type":"WebSite","@id":"https:\/\/www.silicloud.com\/blog\/#website","url":"https:\/\/www.silicloud.com\/blog\/","name":"Silicon Cloud Blog","description":"","publisher":{"@id":"https:\/\/www.silicloud.com\/blog\/#organization"},"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/www.silicloud.com\/blog\/#organization","name":"Silicon Cloud Blog","url":"https:\/\/www.silicloud.com\/blog\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.silicloud.com\/blog\/#\/schema\/logo\/image\/","url":"https:\/\/www.silicloud.com\/blog\/wp-content\/uploads\/2023\/11\/EN-SILICON-Full.png","contentUrl":"https:\/\/www.silicloud.com\/blog\/wp-content\/uploads\/2023\/11\/EN-SILICON-Full.png","width":1024,"height":1024,"caption":"Silicon Cloud Blog"},"image":{"@id":"https:\/\/www.silicloud.com\/blog\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.facebook.com\/SiliCloudGlobal\/","https:\/\/twitter.com\/SiliCloudGlobal"]},{"@type":"Person","@id":"https:\/\/www.silicloud.com\/blog\/#\/schema\/person\/f697031891aacefc4b681d139781d3c0","name":"William Carter","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.silicloud.com\/blog\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/1786698071dd8d74bec894b512f9e3c610c3a2a32985f67e688976cee3c8bbef?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/1786698071dd8d74bec894b512f9e3c610c3a2a32985f67e688976cee3c8bbef?s=96&d=mm&r=g","caption":"William Carter"},"url":"https:\/\/www.silicloud.com\/blog\/author\/williamcarter\/"}]}},"_links":{"self":[{"href":"https:\/\/www.silicloud.com\/blog\/wp-json\/wp\/v2\/posts\/2008","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.silicloud.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.silicloud.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.silicloud.com\/blog\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/www.silicloud.com\/blog\/wp-json\/wp\/v2\/comments?post=2008"}],"version-history":[{"count":3,"href":"https:\/\/www.silicloud.com\/blog\/wp-json\/wp\/v2\/posts\/2008\/revisions"}],"predecessor-version":[{"id":72087,"href":"https:\/\/www.silicloud.com\/blog\/wp-json\/wp\/v2\/posts\/2008\/revisions\/72087"}],"wp:attachment":[{"href":"https:\/\/www.silicloud.com\/blog\/wp-json\/wp\/v2\/media?parent=2008"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.silicloud.com\/blog\/wp-json\/wp\/v2\/categories?post=2008"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.silicloud.com\/blog\/wp-json\/wp\/v2\/tags?post=2008"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}