代码模板-C语言常用的errno的名字、值以及对应关系？转换字符串函数？（errno.h, strerror； errno -l； man errno）

背景

errno.h是C 编程语言标准库中的头文件。它定义了使用符号errno （“错误号”的缩写）报告和检索错误情况的宏。经常需要用来在内核态用户态返回错误寻找，本文以供快速检索。

常用函数与用法

strerror 根据errno获取文件

比如：

    FILE *file = fopen("non_file.txt", "r");if (file == NULL) {// 输出错误信息printf("Error opening file: %s\n", strerror(errno));return EXIT_FAILURE;}

实战输出：

函数返回

某个地方执行事务可以直接用 return -Exxx 这里的Exxx就是下面的 errorno的宏定义， 比如return -EPERM;表示没有权限

头文件

errno.h

对应关系

#define	EPERM 1		/* Not super-user */
#define	ENOENT 2	/* No such file or directory */
#define	ESRCH 3		/* No such process */
#define	EINTR 4		/* Interrupted system call */
#define	EIO 5		/* I/O error */
#define	ENXIO 6		/* No such device or address */
#define	E2BIG 7		/* Arg list too long */
#define	ENOEXEC 8	/* Exec format error */
#define	EBADF 9		/* Bad file number */
#define	ECHILD 10	/* No children */
#define	EAGAIN 11	/* No more processes */
#define	ENOMEM 12	/* Not enough core */
#define	EACCES 13	/* Permission denied */
#define	EFAULT 14	/* Bad address */
#define	ENOTBLK 15	/* Block device required */
#define	EBUSY 16	/* Mount device busy */
#define	EEXIST 17	/* File exists */
#define	EXDEV 18	/* Cross-device link */
#define	ENODEV 19	/* No such device */
#define	ENOTDIR 20	/* Not a directory */
#define	EISDIR 21	/* Is a directory */
#define	EINVAL 22	/* Invalid argument */
#define	ENFILE 23	/* Too many open files in system */
#define	EMFILE 24	/* Too many open files */
#define	ENOTTY 25	/* Not a typewriter */
#define	ETXTBSY 26	/* Text file busy */
#define	EFBIG 27	/* File too large */
#define	ENOSPC 28	/* No space left on device */
#define	ESPIPE 29	/* Illegal seek */
#define	EROFS 30	/* Read only file system */
#define	EMLINK 31	/* Too many links */
#define	EPIPE 32	/* Broken pipe */
#define	EDOM 33		/* Math arg out of domain of func */
#define	ERANGE 34	/* Math result not representable */
#define	ENOMSG 35	/* No message of desired type */
#define	EIDRM 36	/* Identifier removed */
#define	ECHRNG 37	/* Channel number out of range */
#define	EL2NSYNC 38	/* Level 2 not synchronized */
#define	EL3HLT 39	/* Level 3 halted */
#define	EL3RST 40	/* Level 3 reset */
#define	ELNRNG 41	/* Link number out of range */
#define	EUNATCH 42	/* Protocol driver not attached */
#define	ENOCSI 43	/* No CSI structure available */
#define	EL2HLT 44	/* Level 2 halted */
#define	EDEADLK 45	/* Deadlock condition */
#define	ENOLCK 46	/* No record locks available */
#define EBADE 50	/* Invalid exchange */
#define EBADR 51	/* Invalid request descriptor */
#define EXFULL 52	/* Exchange full */
#define ENOANO 53	/* No anode */
#define EBADRQC 54	/* Invalid request code */
#define EBADSLT 55	/* Invalid slot */
#define EDEADLOCK 56	/* File locking deadlock error */
#define EBFONT 57	/* Bad font file fmt */
#define ENOSTR 60	/* Device not a stream */
#define ENODATA 61	/* No data (for no delay io) */
#define ETIME 62	/* Timer expired */
#define ENOSR 63	/* Out of streams resources */
#define ENONET 64	/* Machine is not on the network */
#define ENOPKG 65	/* Package not installed */
#define EREMOTE 66	/* The object is remote */
#define ENOLINK 67	/* The link has been severed */
#define EADV 68		/* Advertise error */
#define ESRMNT 69	/* Srmount error */
#define	ECOMM 70	/* Communication error on send */
#define EPROTO 71	/* Protocol error */
#define	EMULTIHOP 74	/* Multihop attempted */
#define	ELBIN 75	/* Inode is remote (not really error) */
#define	EDOTDOT 76	/* Cross mount point (not really error) */
#define EBADMSG 77	/* Trying to read unreadable message */
#define EFTYPE 79	/* Inappropriate file type or format */
#define ENOTUNIQ 80	/* Given log. name not unique */
#define EBADFD 81	/* f.d. invalid for this operation */
#define EREMCHG 82	/* Remote address changed */
#define ELIBACC 83	/* Can't access a needed shared lib */
#define ELIBBAD 84	/* Accessing a corrupted shared lib */
#define ELIBSCN 85	/* .lib section in a.out corrupted */
#define ELIBMAX 86	/* Attempting to link in too many libs */
#define ELIBEXEC 87	/* Attempting to exec a shared library */
#define ENOSYS 88	/* Function not implemented */
#define ENMFILE 89      /* No more files */
#define ENOTEMPTY 90	/* Directory not empty */
#define ENAMETOOLONG 91	/* File or path name too long */
#define ELOOP 92	/* Too many symbolic links */
#define EOPNOTSUPP 95	/* Operation not supported on transport endpoint */
#define EPFNOSUPPORT 96 /* Protocol family not supported */
#define ECONNRESET 104  /* Connection reset by peer */
#define ENOBUFS 105	/* No buffer space available */
#define EAFNOSUPPORT 106 /* Address family not supported by protocol family */
#define EPROTOTYPE 107	/* Protocol wrong type for socket */
#define ENOTSOCK 108	/* Socket operation on non-socket */
#define ENOPROTOOPT 109	/* Protocol not available */
#define ESHUTDOWN 110	/* Can't send after socket shutdown */
#define ECONNREFUSED 111	/* Connection refused */
#define EADDRINUSE 112		/* Address already in use */
#define ECONNABORTED 113	/* Connection aborted */
#define ENETUNREACH 114		/* Network is unreachable */
#define ENETDOWN 115		/* Network interface is not configured */
#define ETIMEDOUT 116		/* Connection timed out */
#define EHOSTDOWN 117		/* Host is down */
#define EHOSTUNREACH 118	/* Host is unreachable */
#define EINPROGRESS 119		/* Connection already in progress */
#define EALREADY 120		/* Socket already connected */
#define EDESTADDRREQ 121	/* Destination address required */
#define EMSGSIZE 122		/* Message too long */
#define EPROTONOSUPPORT 123	/* Unknown protocol */
#define ESOCKTNOSUPPORT 124	/* Socket type not supported */
#define EADDRNOTAVAIL 125	/* Address not available */
#define ENETRESET 126
#define EISCONN 127		/* Socket is already connected */
#define ENOTCONN 128		/* Socket is not connected */
#define ETOOMANYREFS 129
#define EPROCLIM 130
#define EUSERS 131
#define EDQUOT 132
#define ESTALE 133
#define ENOTSUP 134		/* Not supported */
#define ENOMEDIUM 135   /* No medium (in tape drive) */
#define ENOSHARE 136    /* No such host or network path */
#define ECASECLASH 137  /* Filename exists with different case */
#define EILSEQ 138
#define EOVERFLOW 139	/* Value too large for defined data type */

POSIX中的errno

Symbol	Value	Description
EPERM	1	Operation not permitted
ENOENT	2	No such file or directory
ESRCH	3	No such process
EINTR	4	Interrupted system call
EIO	5	Input/output error
ENXIO	6	No such device or address
E2BIG	7	Argument list too long
ENOEXEC	8	Exec format error
EBADF	9	Bad file descriptor
ECHILD	10	No child processes
EAGAIN	11	Resource temporarily unavailable
ENOMEM	12	Cannot allocate memory
EACCES	13	Permission denied
EFAULT	14	Bad address
ENOTBLK	15	Block device required
EBUSY	16	Device or resource busy
EEXIST	17	File exists
EXDEV	18	Invalid cross-device link
ENODEV	19	No such device
ENOTDIR	20	Not a directory
EISDIR	21	Is a directory
EINVAL	22	Invalid argument
ENFILE	23	Too many open files in system
EMFILE	24	Too many open files
ENOTTY	25	Inappropriate ioctl for device
ETXTBSY	26	Text file busy
EFBIG	27	File too large
ENOSPC	28	No space left on device
ESPIPE	29	Illegal seek
EROFS	30	Read-only file system
EMLINK	31	Too many links
EPIPE	32	Broken pipe
EDOM	33	Numerical argument out of domain
ERANGE	34	Numerical result out of range
EDEADLK	35	Resource deadlock avoided
ENAMETOOLONG	36	File name too long
ENOLCK	37	No locks available
ENOSYS	38	Function not implemented
ENOTEMPTY	39	Directory not empty
ELOOP	40	Too many levels of symbolic links
ENOMSG	42	No message of desired type
EIDRM	43	Identifier removed
ECHRNG	44	Channel number out of range
EL2NSYNC	45	Level 2 not synchronized
EL3HLT	46	Level 3 halted
EL3RST	47	Level 3 reset
ELNRNG	48	Link number out of range
EUNATCH	49	Protocol driver not attached
ENOCSI	50	No CSI structure available
EL2HLT	51	Level 2 halted
EBADE	52	Invalid exchange
EBADR	53	Invalid request descriptor
EXFULL	54	Exchange full
ENOANO	55	No anode
EBADRQC	56	Invalid request code
EBADSLT	57	Invalid slot
EBFONT	59	Bad font file format
ENOSTR	60	Device not a stream
ENODATA	61	No data available
ETIME	62	Timer expired
ENOSR	63	Out of streams resources
ENONET	64	Machine is not on the network
ENOPKG	65	Package not installed
EREMOTE	66	Object is remote
ENOLINK	67	Link has been severed
EADV	68	Advertise error
ESRMNT	69	Srmount error
ECOMM	70	Communication error on send
EPROTO	71	Protocol error
EMULTIHOP	72	Multihop attempted
EDOTDOT	73	RFS specific error
EBADMSG	74	Bad message
EOVERFLOW	75	Value too large for defined data type
ENOTUNIQ	76	Name not unique on network
EBADFD	77	File descriptor in bad state
EREMCHG	78	Remote address changed
ELIBACC	79	Can not access a needed shared library
ELIBBAD	80	Accessing a corrupted shared library
ELIBSCN	81	.lib section in a.out corrupted
ELIBMAX	82	Attempting to link in too many shared libraries
ELIBEXEC	83	Cannot exec a shared library directly
EILSEQ	84	Invalid or incomplete multibyte or wide character
ERESTART	85	Interrupted system call should be restarted
ESTRPIPE	86	Streams pipe error
EUSERS	87	Too many users
ENOTSOCK	88	Socket operation on non-socket
EDESTADDRREQ	89	Destination address required
EMSGSIZE	90	Message too long
EPROTOTYPE	91	Protocol wrong type for socket
ENOPROTOOPT	92	Protocol not available
EPROTONOSUPPORT	93	Protocol not supported
ESOCKTNOSUPPORT	94	Socket type not supported
EOPNOTSUPP	95	Operation not supported
EPFNOSUPPORT	96	Protocol family not supported
EAFNOSUPPORT	97	Address family not supported by protocol
EADDRINUSE	98	Address already in use
EADDRNOTAVAIL	99	Cannot assign requested address
ENETDOWN	100	Network is down
ENETUNREACH	101	Network is unreachable
ENETRESET	102	Network dropped connection on reset
ECONNABORTED	103	Software caused connection abort
ECONNRESET	104	Connection reset by peer
ENOBUFS	105	No buffer space available
EISCONN	106	Transport endpoint is already connected
ENOTCONN	107	Transport endpoint is not connected
ESHUTDOWN	108	Cannot send after transport endpoint shutdown
ETOOMANYREFS	109	Too many references: cannot splice
ETIMEDOUT	110	Connection timed out
ECONNREFUSED	111	Connection refused
EHOSTDOWN	112	Host is down
EHOSTUNREACH	113	No route to host
EALREADY	114	Operation already in progress
EINPROGRESS	115	Operation now in progress
ESTALE	116	Stale file handle
EUCLEAN	117	Structure needs cleaning
ENOTNAM	118	Not a XENIX named type file
ENAVAIL	119	No XENIX semaphores available
EISNAM	120	Is a named type file
EREMOTEIO	121	Remote I/O error
EDQUOT	122	Disk quota exceeded
ENOMEDIUM	123	No medium found
EMEDIUMTYPE	124	Wrong medium type
ECANCELED	125	Operation canceled
ENOKEY	126	Required key not available
EKEYEXPIRED	127	Key has expired
EKEYREVOKED	128	Key has been revoked
EKEYREJECTED	129	Key was rejected by service
EOWNERDEAD	130	Owner died
ENOTRECOVERABLE	131	State not recoverable
ERFKILL	132	Operation not possible due to RF-kill
EHWPOISON	133	Memory page has hardware error

其他获取方式

man手册获取 man errno

还可以通过man手册动态获取，命令：man errno

使用errno命令获取 errno -l

如果没有需要安装比如ubuntu是 moreutils安装包：apt install moreutils

• 安装moreutils包安装errno命令
  
• errno -l 查看输出
  

参考：
https://en.wikipedia.org/wiki/Errno.h