Question: “is malloc reentrant”?
\nAnswer: no, it is not. Here is one definition of what makes a routine reentrant.<\/p>\n
None of the common versions of malloc allow you to reenter it (e.g. from signal handler). Note that a reentrant routine may not use locks, and almost all malloc versions in existence do use locks (which makes them thread-safe), or global\/static variables (which makes them thread-unsafe and<\/em> non-reentrant).<\/p>\n All the answers so far answer “is malloc thread-safe?”, which is entirely different question. To that<\/em> question the answer is it depends<\/em> on your runtime library, and possibly on the compiler flags you use. On any modern UNIX you’ll get a thread-safe malloc by default. On Windows, use Question: “is malloc reentrant”? Answer: no, it is not. Here is one definition of what makes a routine reentrant. None of the common versions of malloc allow you to reenter it (e.g. from signal handler). Note that a reentrant routine may not use locks, and almost all malloc versions in existence do use locks (which […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-5119","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/posts\/5119","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/comments?post=5119"}],"version-history":[{"count":0,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/posts\/5119\/revisions"}],"wp:attachment":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/media?parent=5119"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/categories?post=5119"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/tags?post=5119"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}\/MT<\/code>, \/MTd<\/code>, \/MD<\/code> or \/MDd<\/code> flags to get thread-safe runtime library.<\/p>\n","protected":false},"excerpt":{"rendered":"