mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| t |
| t2 |
| test |
+----------------+
3 rows in set (0.00 sec)
mysql> show tables as c;
ERROR 1064 (42000): You have an error in your SQL syntax;
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我想恢复名为列的结果c,但如您所见,这是语法错误...
有没有办法做到这一点?
5 enum state {ST_BEFORE_KEY, ST_IN_KEY, ST_BEFORE_VALUE, ST_TERM, ST_ERR};
6
7 typedef struct {
8 state st;
...
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以上代码报告:
error: expected specifier-qualifier-list before ‘state’
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使用枚举类型有什么问题?
我正在尝试getoptAPI:
http://www.gnu.org/s/hello/manual/libc/Example-of-Getopt.html#Example-of-Getopt
但我觉得它只支持中间的选项?
当我发现它的判断argv[optind],以argv[argc-1]非选择的参数.
是这样的吗?
假设有标志定义,例如:
SHF_WRITE 0x1
SHF_ALLOC 0x2
SHF_EXECINSTR 0x4
SHF_MASKPROC 0xf0000000
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给定一个标志,我需要输出SHF_WRITE|SHF_ALLOC比特0x1并0x2打开.
怎么用C做的伎俩?