c11

问题 This question already has answers here : Can sizeof(int) ever be 1 on a hosted implementation? (8 answers) Closed 5 years ago . According to the C standard, any characters returned by fgetc are returned in the form of unsigned char values, "converted to an int " (that quote comes from the C standard, stating that there is indeed a conversion). When sizeof (int) == 1 , many unsigned char values are outside of range. It is thus possible that some of those unsigned char values might end up being

问题 I believe the title is self-explanatory, but here's an example to illustrate what I'm trying to accomplish: #define PASTE2(_0, _1) _0 ## _1 #define DEFINE_OPS_FOR_TYPE(TYPE) \ int PASTE2(do_something_with_, TYPE)(void) { \ /* do_something_with_<TYPE> */ \ } Everything works fine for char , int , and single-worded types, but when it comes to unsigned types, or others that have multiple keywords, using token pasting ( a ## b ) does not generate a valid name due to the whitespace (e.g.: do

问题 Closed . This question is opinion-based. It is not currently accepting answers. Want to improve this question? Update the question so it can be answered with facts and citations by editing this post. Closed 3 years ago . Improve this question What is unsafe with fopen that's more safe with fopen_s ? How can fopen be used in a safe way (if possible)? (I don't want to know how to suppress the warning - there are enough stackoverflow articles that answer that question) Edit: Question was closed

问题 Closed . This question is opinion-based. It is not currently accepting answers. Want to improve this question? Update the question so it can be answered with facts and citations by editing this post. Closed 3 years ago . Improve this question What is unsafe with fopen that's more safe with fopen_s ? How can fopen be used in a safe way (if possible)? (I don't want to know how to suppress the warning - there are enough stackoverflow articles that answer that question) Edit: Question was closed

问题 Section 6.8.1 of C11 or C99, or section 3.6.1 of C89 all seem to indicate that default and case x (where x is some constant-expression ) are examples of labeled statements, along-side identifier: -style labels that are suitable for use with goto . I'm aware that I could simply place an identifier: -style label directly following the default: or case x: labels. That's not what this question is about. I'm more curious as to whether there is any actual rationale behind prohibiting this kind of

问题 Section 6.8.1 of C11 or C99, or section 3.6.1 of C89 all seem to indicate that default and case x (where x is some constant-expression ) are examples of labeled statements, along-side identifier: -style labels that are suitable for use with goto . I'm aware that I could simply place an identifier: -style label directly following the default: or case x: labels. That's not what this question is about. I'm more curious as to whether there is any actual rationale behind prohibiting this kind of

问题 Section 6.8.1 of C11 or C99, or section 3.6.1 of C89 all seem to indicate that default and case x (where x is some constant-expression ) are examples of labeled statements, along-side identifier: -style labels that are suitable for use with goto . I'm aware that I could simply place an identifier: -style label directly following the default: or case x: labels. That's not what this question is about. I'm more curious as to whether there is any actual rationale behind prohibiting this kind of

问题 I'm new to C, and I think there may be an issue with pointers here. Any help would be appreciated! I have a linkedlist struct that looks like this: ll.h: #ifndef LLTEST_LL_H #define LLTEST_LL_H #include <stdlib.h> typedef struct _listNode { void *data; struct _listNode *next; } listNode; typedef struct { int logicalLength; int elementSize; listNode *head; listNode *tail; } linkedlist; typedef struct table { const char* name; size_t col_count; size_t length; } table; typedef struct db { const

问题 Answers to this and this question say that function pointers of the form return-type (*pointer)() are pointers to a function which takes any number of arguments, though the latter says they obsolesced in C11. On an i386 system with GCC, “extra” arguments passed in a call to an empty-parentheses-type’d function pointer are ignored, because of how stack frames work; e.g., /* test.c */ #include <stdio.h> int foo(int arg) { return arg; } int main(void) { int (*fp)() = foo; printf("%d\n", fp

问题 I'm under the impression my C compiler supports C11 since it accepts the -std=c11 flag, $ cc --version Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn) Target: x86_64-apple-darwin13.3.0 Thread model: posix and uchar.h is part of the C11 standard, so I'd expect this program to compile, $ cat /tmp/esc.c #include <uchar.h> int main(void) {} But $ cc /tmp/esc.c /tmp/esc.c:1:10: fatal error: 'uchar.h' file not found #include <uchar.h> ^ 1 error generated. I tried locating the uchar.h