{"id":4932,"date":"2014-04-18T11:07:50","date_gmt":"2014-04-18T16:07:50","guid":{"rendered":"httpss:\/\/www.powenko.com\/wordpress\/?p=4932"},"modified":"2014-04-18T11:08:49","modified_gmt":"2014-04-18T16:08:49","slug":"2-copy_to_user-%e5%af%ab%e5%85%a5%e8%b3%87%e6%96%99","status":"publish","type":"post","link":"https:\/\/www.powenko.com\/wordpress\/?p=4932","title":{"rendered":"02. copy_to_user \u5beb\u5165\u8cc7\u6599"},"content":{"rendered":"<pre class=\"brush: php; title: ; notranslate\" title=\"\">\r\nchar *memory_buffer;\r\nssize_t memory_read(struct file *filp, char *buf, \r\n                    size_t count, loff_t *f_pos) { \r\n \r\n  \/* Transfering data to user space *\/ \r\n  if(memory_buffer==null){\r\n      memory_buffer = kmalloc(1, GFP_KERNEL);\r\n  }\r\n  copy_to_user(buf,memory_buffer,1);\r\n\r\n  \/* Changing reading position as best suits *\/ \r\n  if (*f_pos == 0) { \r\n    *f_pos+=1; \r\n    return 1; \r\n  } else { \r\n    return 0; \r\n  }\r\n}\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>char *memory_buffer; ssize_t memory_read(struct file *f [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[202],"tags":[],"class_list":["post-4932","post","type-post","status-publish","format-standard","hentry","category-ch03-"],"_links":{"self":[{"href":"https:\/\/www.powenko.com\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4932"}],"collection":[{"href":"https:\/\/www.powenko.com\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.powenko.com\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.powenko.com\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.powenko.com\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4932"}],"version-history":[{"count":2,"href":"https:\/\/www.powenko.com\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4932\/revisions"}],"predecessor-version":[{"id":4934,"href":"https:\/\/www.powenko.com\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4932\/revisions\/4934"}],"wp:attachment":[{"href":"https:\/\/www.powenko.com\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4932"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.powenko.com\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4932"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.powenko.com\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4932"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}