{"id":28784,"date":"2023-01-02T23:39:48","date_gmt":"2023-01-02T18:09:48","guid":{"rendered":"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/"},"modified":"2023-01-02T23:39:48","modified_gmt":"2023-01-02T18:09:48","slug":"solved-read-access-privilage-of-last-5-elements","status":"publish","type":"post","link":"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/","title":{"rendered":"[Solved] Read access privilage of last 5 elements"},"content":{"rendered":"

[ad_1]
\n<\/p>\n

\n
\n
<\/div>\n
\n
\n

I am assuming your arr<\/code> is a POD (plain old data) array. You could make it in C++ a class and overload the operator[]<\/code> to do runtime index checking.<\/p>\n

You usually cannot do what you want, and if you could, it would be strongly implementation and operating system dependent.<\/p>\n

On Linux, access permission to data is related to virtual memory<\/a> mapping. This is related to the mmap(2) and munmap(2)<\/a> with mprotect(2)<\/a> system call. These calls work at a page-level granularity (a page is usually 4Kbytes, and 4Kbytes aligned).<\/p>\n

You could make naughty tricks like mmap<\/code>-ing a large region, mprotect<\/code> its last page, and do unportable pointer arithmetic to compute the arr<\/code> pointer. This is disgusting, so don’t do that. And catching SIGSEGV<\/code> with dirty mmap<\/code>-based tricks like this is not very portable and probably not very efficient. And a signal handler cannot throw C++ exceptions.<\/p>\n<\/p><\/div>\n

<\/div>\n<\/div>\n

<\/span> <\/p><\/div>\n<\/div>\n

[ad_2]<\/p>\n

solved Read access privilage of last 5 elements <\/p>\n","protected":false},"excerpt":{"rendered":"

[ad_1] I am assuming your arr is a POD (plain old data) array. You could make it in C++ a class and overload the operator[] to do runtime index checking. You usually cannot do what you want, and if you could, it would be strongly implementation and operating system dependent. On Linux, access permission to … Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[320],"tags":[361,324,412,325],"class_list":["post-28784","post","type-post","status-publish","format-standard","hentry","category-solved","tag-arrays","tag-c","tag-error-handling","tag-performance"],"yoast_head":"\n[Solved] Read access privilage of last 5 elements - JassWeb<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"[Solved] Read access privilage of last 5 elements - JassWeb\" \/>\n<meta property=\"og:description\" content=\"[ad_1] I am assuming your arr is a POD (plain old data) array. You could make it in C++ a class and overload the operator[] to do runtime index checking. You usually cannot do what you want, and if you could, it would be strongly implementation and operating system dependent. On Linux, access permission to ... Read more\" \/>\n<meta property=\"og:url\" content=\"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/\" \/>\n<meta property=\"og:site_name\" content=\"JassWeb\" \/>\n<meta property=\"article:published_time\" content=\"2023-01-02T18:09:48+00:00\" \/>\n<meta name=\"author\" content=\"Kirat\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Kirat\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/#article\",\"isPartOf\":{\"@id\":\"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/\"},\"author\":{\"name\":\"Kirat\",\"@id\":\"https:\/\/jassweb.com\/solved\/#\/schema\/person\/65c9c7b7958150c0dc8371fa35dd7c31\"},\"headline\":\"[Solved] Read access privilage of last 5 elements\",\"datePublished\":\"2023-01-02T18:09:48+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/\"},\"wordCount\":157,\"publisher\":{\"@id\":\"https:\/\/jassweb.com\/solved\/#organization\"},\"keywords\":[\"arrays\",\"c++\",\"error-handling\",\"performance\"],\"articleSection\":[\"Solved\"],\"inLanguage\":\"en-US\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/\",\"url\":\"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/\",\"name\":\"[Solved] Read access privilage of last 5 elements - JassWeb\",\"isPartOf\":{\"@id\":\"https:\/\/jassweb.com\/solved\/#website\"},\"datePublished\":\"2023-01-02T18:09:48+00:00\",\"breadcrumb\":{\"@id\":\"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/jassweb.com\/solved\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"[Solved] Read access privilage of last 5 elements\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/jassweb.com\/solved\/#website\",\"url\":\"https:\/\/jassweb.com\/solved\/\",\"name\":\"JassWeb\",\"description\":\"Build High-quality Websites\",\"publisher\":{\"@id\":\"https:\/\/jassweb.com\/solved\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/jassweb.com\/solved\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\/\/jassweb.com\/solved\/#organization\",\"name\":\"Jass Web\",\"url\":\"https:\/\/jassweb.com\/solved\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/jassweb.com\/solved\/#\/schema\/logo\/image\/\",\"url\":\"https:\/\/jassweb.com\/wp-content\/uploads\/2021\/02\/jass-website-logo-1.png\",\"contentUrl\":\"https:\/\/jassweb.com\/wp-content\/uploads\/2021\/02\/jass-website-logo-1.png\",\"width\":693,\"height\":132,\"caption\":\"Jass Web\"},\"image\":{\"@id\":\"https:\/\/jassweb.com\/solved\/#\/schema\/logo\/image\/\"}},{\"@type\":\"Person\",\"@id\":\"https:\/\/jassweb.com\/solved\/#\/schema\/person\/65c9c7b7958150c0dc8371fa35dd7c31\",\"name\":\"Kirat\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/jassweb.com\/solved\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/jassweb.com\/solved\/wp-content\/litespeed\/avatar\/1261af3c9451399fa1336d28b98ea3bb.jpg?ver=1776403586\",\"contentUrl\":\"https:\/\/jassweb.com\/solved\/wp-content\/litespeed\/avatar\/1261af3c9451399fa1336d28b98ea3bb.jpg?ver=1776403586\",\"caption\":\"Kirat\"},\"sameAs\":[\"http:\/\/jassweb.com\"],\"url\":\"https:\/\/jassweb.com\/solved\/author\/jaspritsinghghumangmail-com\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"[Solved] Read access privilage of last 5 elements - JassWeb","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:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/","og_locale":"en_US","og_type":"article","og_title":"[Solved] Read access privilage of last 5 elements - JassWeb","og_description":"[ad_1] I am assuming your arr is a POD (plain old data) array. You could make it in C++ a class and overload the operator[] to do runtime index checking. You usually cannot do what you want, and if you could, it would be strongly implementation and operating system dependent. On Linux, access permission to ... Read more","og_url":"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/","og_site_name":"JassWeb","article_published_time":"2023-01-02T18:09:48+00:00","author":"Kirat","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Kirat","Est. reading time":"1 minute"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/#article","isPartOf":{"@id":"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/"},"author":{"name":"Kirat","@id":"https:\/\/jassweb.com\/solved\/#\/schema\/person\/65c9c7b7958150c0dc8371fa35dd7c31"},"headline":"[Solved] Read access privilage of last 5 elements","datePublished":"2023-01-02T18:09:48+00:00","mainEntityOfPage":{"@id":"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/"},"wordCount":157,"publisher":{"@id":"https:\/\/jassweb.com\/solved\/#organization"},"keywords":["arrays","c++","error-handling","performance"],"articleSection":["Solved"],"inLanguage":"en-US"},{"@type":"WebPage","@id":"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/","url":"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/","name":"[Solved] Read access privilage of last 5 elements - JassWeb","isPartOf":{"@id":"https:\/\/jassweb.com\/solved\/#website"},"datePublished":"2023-01-02T18:09:48+00:00","breadcrumb":{"@id":"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/jassweb.com\/solved\/solved-read-access-privilage-of-last-5-elements\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/jassweb.com\/solved\/"},{"@type":"ListItem","position":2,"name":"[Solved] Read access privilage of last 5 elements"}]},{"@type":"WebSite","@id":"https:\/\/jassweb.com\/solved\/#website","url":"https:\/\/jassweb.com\/solved\/","name":"JassWeb","description":"Build High-quality Websites","publisher":{"@id":"https:\/\/jassweb.com\/solved\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/jassweb.com\/solved\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/jassweb.com\/solved\/#organization","name":"Jass Web","url":"https:\/\/jassweb.com\/solved\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/jassweb.com\/solved\/#\/schema\/logo\/image\/","url":"https:\/\/jassweb.com\/wp-content\/uploads\/2021\/02\/jass-website-logo-1.png","contentUrl":"https:\/\/jassweb.com\/wp-content\/uploads\/2021\/02\/jass-website-logo-1.png","width":693,"height":132,"caption":"Jass Web"},"image":{"@id":"https:\/\/jassweb.com\/solved\/#\/schema\/logo\/image\/"}},{"@type":"Person","@id":"https:\/\/jassweb.com\/solved\/#\/schema\/person\/65c9c7b7958150c0dc8371fa35dd7c31","name":"Kirat","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/jassweb.com\/solved\/#\/schema\/person\/image\/","url":"https:\/\/jassweb.com\/solved\/wp-content\/litespeed\/avatar\/1261af3c9451399fa1336d28b98ea3bb.jpg?ver=1776403586","contentUrl":"https:\/\/jassweb.com\/solved\/wp-content\/litespeed\/avatar\/1261af3c9451399fa1336d28b98ea3bb.jpg?ver=1776403586","caption":"Kirat"},"sameAs":["http:\/\/jassweb.com"],"url":"https:\/\/jassweb.com\/solved\/author\/jaspritsinghghumangmail-com\/"}]}},"_links":{"self":[{"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/posts\/28784","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/comments?post=28784"}],"version-history":[{"count":0,"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/posts\/28784\/revisions"}],"wp:attachment":[{"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/media?parent=28784"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/categories?post=28784"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/tags?post=28784"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}