errno的基本用法
error是一个包含在<errno.h>中的预定义的外部int变量,用于表示最近一个函数调用是否产生了错误。若为0,则无错误,其它值均表示一类错误。
perror()和strerrot()函数可以把errno的值转化为有意义的字符输出。
#include <stdio.h>
#include <stdlib.h>
#include <dirent.h>
#include <errno.h>
#include <string.h>
int main(void){
extern int errno;
errno=0;
opendir("/home/kkk");
//用法1:直接读取errno的值
printf("%d\n", errno);
//用法2:使用perror函数,把error的值转化为有意义的字符提示。
if(errno != 0){
perror("opendir: ");
// exit(EXIT_FAILURE);
}
//用法3:类似用法2,但使用strerror函数。
if(errno != 0){
printf("%s\n", strerror(errno));
exit(0);
}
exit(0);
}
输出结果为:
2
opendir: : No such file or directory
No such file or directory
以下程序用于显示所有的错误代码含义(经测试,目前的错误代码从0-132,其余未使用)
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
int main(void){
for(int i = 0; i < 140; i++){
printf("%4d:%s\n", i, strerror(i));
}
exit(0);
}
输出结果如下:
0:Success
1:Operation not permitted
2:No such file or directory
3:No such process
4:Interrupted system call
5:Input/output error
6:No such device or address
7:Argument list too long
8:Exec format error
9:Bad file descriptor
10:No child processes
11:Resource temporarily unavailable
12:Cannot allocate memory
13:Permission denied
14:Bad address
15:Block device required
16:Device or resource busy
17:File exists
18:Invalid cross-device link
19:No such device
20:Not a directory
21:Is a directory
22:Invalid argument
23:Too many open files in system
24:Too many open files
25:Inappropriate ioctl for device
26:Text file busy
27:File too large
28:No space left on device
29:Illegal seek
30:Read-only file system
31:Too many links
32:Broken pipe
33:Numerical argument out of domain
34:Numerical result out of range
35:Resource deadlock avoided
36:File name too long
37:No locks available
38:Function not implemented
39:Directory not empty
40:Too many levels of symbolic links
41:Unknown error 41
42:No message of desired type
43:Identifier removed
44:Channel number out of range
45:Level 2 not synchronized
46:Level 3 halted
47:Level 3 reset
48:Link number out of range
49:Protocol driver not attached
50:No CSI structure available
51:Level 2 halted
52:Invalid exchange
53:Invalid request descriptor
54:Exchange full
55:No anode
56:Invalid request code
57:Invalid slot
58:Unknown error 58
59:Bad font file format
60:Device not a stream
61:No data available
62:Timer expired
63:Out of streams resources
64:Machine is not on the network
65:Package not installed
66:Object is remote
67:Link has been severed
68:Advertise error
69:Srmount error
70:Communication error on send
71:Protocol error
72:Multihop attempted
73:RFS specific error
74:Bad message
75:Value too large for defined data type
76:Name not unique on network
77:File descriptor in bad state
78:Remote address changed
79:Can not access a needed shared library
80:Accessing a corrupted shared library
81:.lib section in a.out corrupted
82:Attempting to link in too many shared libraries
83:Cannot exec a shared library directly
84:Invalid or incomplete multibyte or wide character
85:Interrupted system call should be restarted
86:Streams pipe error
87:Too many users
88:Socket operation on non-socket
89:Destination address required
90:Message too long
91:Protocol wrong type for socket
92:Protocol not available
93:Protocol not supported
94:Socket type not supported
95:Operation not supported
96:Protocol family not supported
97:Address family not supported by protocol
98:Address already in use
99:Cannot assign requested address
100:Network is down
101:Network is unreachable
102:Network dropped connection on reset
103:Software caused connection abort
104:Connection reset by peer
105:No buffer space available
106:Transport endpoint is already connected
107:Transport endpoint is not connected
108:Cannot send after transport endpoint shutdown
109:Too many references: cannot splice
110:Connection timed out
111:Connection refused
112:Host is down
113:No route to host
114:Operation already in progress
115:Operation now in progress
116:Stale NFS file handle
117:Structure needs cleaning
118:Not a XENIX named type file
119:No XENIX semaphores available
120:Is a named type file
121:Remote I/O error
122:Disk quota exceeded
123:No medium found
124:Wrong medium type
125:Operation canceled
126:Required key not available
127:Key has expired
128:Key has been revoked
129:Key was rejected by service
130:Owner died
131:State not recoverable
132:Operation not possible due to RF-kill
133:Unknown error 133
134:Unknown error 134
135:Unknown error 135
136:Unknown error 136
137:Unknown error 137
138:Unknown error 138
139:Unknown error 139
errno的基本用法的更多相关文章
- 附录二 C语言标准库
上章回顾 数组和指针相同与不同 通过指针访问数组和通过数组访问指针 指针在什么时候可以加减运算 函数指针的申明和调用 函数数组和数组函数 git@github.com:Kevin-Dfg/Data-S ...
- errno的用法
Linux中系统调用的错误都存储于 errno中,errno由操作系统维护,存储就近发生的错误,即下一次的错误码会覆盖掉上一次的错误. 编程时需要包含#include <errno.h>, ...
- awk 用法(使用入门)
转自:http://www.cnblogs.com/emanlee/p/3327576.html awk 用法:awk ' pattern {action} ' 变量名 含义 ARGC 命 ...
- PHP错误处理函数set_error_handler()的用法
定义和用法 set_error_handler() 函数设置用户自定义的错误处理函数. 该函数用于创建运行时期间的用户自己的错误处理方法. 该函数会返回旧的错误处理程序,若失败,则返回 null. 语 ...
- C语言中system()函数的用法总结(转)
system()函数功能强大,很多人用却对它的原理知之甚少先看linux版system函数的源码: #include <sys/types.h> #include <sys/wait ...
- sscanf,sscanf_s及其相关用法
#include<stdio.h> 定义函数 int sscanf (const char *str,const char * format,........); 函数说明 sscanf ...
- awk用法
目前虽然有很多工具可以代替awk,但是呢我还是认为awk还是非常重要,比如有时候load数据到hive,mysql发现数据有点问题,这样可以先对比文件和库中数据是否一致,这样awk就发挥用处了,还有从 ...
- epoll函数与参数总结学习 & errno的线程安全
select/poll被监视的文件描述符数目非常大时要O(n)效率很低:epoll与旧的 select 和 poll 系统调用完成操作所需 O(n) 不同, epoll能在O(1)时间内完成操作,所以 ...
- [转]ORACLE的ProC用法讲解
pro*c是高级的用法,OCI是oracle的基础用法 如何编译.pc文件: proc code=cpp parse=none iname=filename.pc oname=filename.cp ...
随机推荐
- phpcms:三、头部包含
1‘标题:{if isset($SEO['title']) && !empty($SEO['title'])}{$SEO['title']}{/if}{$SEO['site_title ...
- MySQL数据库 常用操作
1:使用SHOW语句找出在服务器上当前存在什么数据库: mysql> SHOW DATABASES; 2:创建一个数据库MYSQLDATA mysql> CREATE DATABASE M ...
- [转] ubuntu 一些常用软件的安装
首先说明一下 ubuntu 的软件安装大概有几种方式: 1. deb 包的安装方式deb 是 debian 系 Linux 的包管理方式, ubuntu 是属于 debian 系的 Linux 发行版 ...
- LDAP协议介绍
LDAP协议基础概念 1. 从用途上阐述LDAP,它是一个存储静态相关信息的服务,适合"一次记录多次读取".经常使用LDAP服务存储的信息: 公司的物理设备信息(如打印机,它的I ...
- [Javascript] Web APIs: Persisting browser data with window.localStorage
Local Storage is a native JavaScript Web API that makes it easy to store and persist data (as key-va ...
- 代码,显示IPhone剩余磁盘空间
#include <sys/mount.h> //这段代码示范怎么取得 iPhone 的剩余磁盘空间,还有全部磁盘空间 long long freeSpace() { struct sta ...
- js获取当前页面的网址域名地址
1.获取当前完整网址thisURL = document.URL;thisHREF = document.location.href;thisSLoc = self.location.href;thi ...
- Android中多表的SQLite数据库(译)
原文: Android SQLite Database with Multiple Tables 在上一篇教程Android SQLite Database Tutorial中,解释了如何在你的And ...
- sql语句的分类
这些天在看Oracle database 11g SQL开发指南,关于sql语句的分类,感觉有必要记录一下. sql语句主要分五类: DML(DATA MANIPULATION LANGUAGE, 数 ...
- Solr中schema.xml的解释
接Solr-4.10.2与Tomcat整合.schema.xml位于D:\solr\data\solr\collection1\conf\中.1.fieldType节点 name: FieldT ...