errno 在 <errno.h> 中定义，错误 Exx 的宏定义在 /usr/include/asm-generic 文件夹下面的 errno-base.h 和 errno.h，分别定义了 1-34 、35-132 的错误定义。
strerror() 函数依据 errno 值返回错误描述字符串，下面程序打印对照表：
[cpp] view plain copy
- #include <errno.h>
- #include <string.h>
- #include <stdio.h>
- int main()
- {
- int i;
- for(i = 0; i < 140; ++i)
- {
- errno = i;
- printf("errno %d :\t\t%s\n",i,strerror(errno));
- }
- return 0;
- }
错误对照表：
errno0 : Success
errno1 : Operation not permitted
errno2 : No such file or directory
errno3 : No such process
errno4 : Interrupted system call
errno5 : Input/output error
errno6 : No such device or address
errno7 : Argument list too long
errno8 : Exec format error
errno9 : Bad file descriptor
errno10 : No child processes
errno11 : Resource temporarily unavailable
errno12 : Cannot allocate memory
errno13 : Permission denied
errno14 : Bad address
errno15 : Block device required
errno16 : Device or resource busy
errno17 : File exists
errno18 : Invalid cross-device link
errno19 : No such device
errno20 : Not a directory
errno21 : Is a directory
errno22 : Invalid argument
errno23 : Too many open files in system
errno24 : Too many open files
errno25 : Inappropriate ioctl for device
errno26 : Text file busy
errno27 : File too large
errno28 : No space left on device
errno29 : Illegal seek
errno30 : Read-only file system
errno31 : Too many links
errno32 : Broken pipe
errno33 : Numerical argument out of domain
errno34 : Numerical result out of range
errno35 : Resource deadlock avoided
errno36 : File name too long
errno37 : No locks available
errno38 : Function not implemented
errno39 : Directory not empty
errno40 : Too many levels of symbolic links
errno41 : Unknown error 41
errno42 : No message of desired type
errno43 : Identifier removed
errno44 : Channel number out of range
errno45 : Level 2 not synchronized
errno46 : Level 3 halted
errno47 : Level 3 reset
errno48 : Link number out of range
errno49 : Protocol driver not attached
errno50 : No CSI structure available
errno51 : Level 2 halted
errno52 : Invalid exchange
errno53 : Invalid request descriptor
errno54 : Exchange full
errno55 : No anode
errno56 : Invalid request code
errno57 : Invalid slot
errno58 : Unknown error 58
errno59 : Bad font file format
errno60 : Device not a stream
errno61 : No data available
errno62 : Timer expired
errno63 : Out of streams resources
errno64 : Machine is not on the network
errno65 : Package not installed
errno66 : Object is remote
errno67 : Link has been severed
errno68 : Advertise error
errno69 : Srmount error
errno70 : Communication error on send
errno71 : Protocol error
errno72 : Multihop attempted
errno73 : RFS specific error
errno74 : Bad message
errno75 : Value too large for defined datatype
errno76 : Name not unique on network
errno77 : File descriptor in bad state
errno78 : Remote address changed
errno79 : Can not access a needed sharedlibrary
errno80 : Accessing a corrupted sharedlibrary
errno81 : .lib section in a.out corrupted
errno82 : Attempting to link in too manyshared libraries
errno83 : Cannot exec a shared librarydirectly
errno84 : Invalid or incomplete multibyte orwide character
errno85 : Interrupted system call should berestarted
errno86 : Streams pipe error
errno87 : Too many users
errno88 : Socket operation on non-socket
errno89 : Destinationaddress required
errno90 : Message too long
errno91 : Protocol wrong type for socket
errno92 : Protocol not available
errno93 : Protocol not supported
errno94 : Socket type not supported
errno95 : Operation not supported
errno96 : Protocol family not supported
errno97 : Address family not supported byprotocol
errno98 : Address already in use
errno99 : Cannot assign requested address
errno100 : Network is down
errno101 : Network is unreachable
errno102 : Network dropped connection onreset
errno103 : Software caused connection abort
errno104 : Connection reset by peer
errno105 : No buffer space available
errno106 : Transport endpoint is alreadyconnected
errno107 : Transport endpoint is notconnected
errno108 : Cannot send after transportendpoint shutdown
errno109 : Too many references: cannot splice
errno110 : Connection timed out
errno111 : Connection refused
errno112 : Host is down
errno113 : No route to host
errno114 : Operation already in progress
errno115 : Operation now in progress
errno116 : Stale NFS file handle
errno117 : Structure needs cleaning
errno118 : Not a XENIX named type file
errno119 : No XENIX semaphores available
errno120 : Is a named type file
errno121 : Remote I/O error
errno122 : Disk quota exceeded
errno123 : No medium found
errno124 : Wrong medium type
errno125 : Operation canceled
errno126 : Required key not available
errno127 : Key has expired
errno128 : Key has been revoked
errno129 : Key was rejected by service
errno130 : Owner died
errno131 : State not recoverable
errno132 : Operation not possible due toRF-kill
errno133 : Unknown error 133
errno134 : Unknown error 134
errno135 : Unknown error 135
errno136 : Unknown error 136
errno137 : Unknown error 137
errno138 : Unknown error 138
errno139 : Unknown error 139
由上可见Linux对错误宏的定义。
头文件 /usr/include/asm-generic/errno-base.h 的源码：
#ifndef _ASM_GENERIC_ERRNO_BASE_H
#define _ASM_GENERIC_ERRNO_BASE_H
#define EPERM 1 /* Operation not permitted */
#define ENOENT2
/* 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 /* Argument list too long */
#define ENOEXEC8
/* Exec format error */
#define EBADF 9 /* Bad file number */
#define ECHILD10
/* No child processes */
#define EAGAIN11
/* Try again */
#define ENOMEM12
/* Out of memory */
#define EACCES13
/* Permission denied */
#define EFAULT14
/* Bad address */
#define ENOTBLK15
/* Block device required */
#define EBUSY 16 /* Device or resource busy */
#define EEXIST17
/* File exists */
#define EXDEV 18 /* Cross-device link */
#define ENODEV19
/* No such device */
#define ENOTDIR20
/* Not a directory */
#define EISDIR21
/* Is a directory */
#define EINVAL22
/* Invalid argument */
#define ENFILE23
/* File table overflow */
#define EMFILE24
/* Too many open files */
#define ENOTTY25
/* Not a typewriter */
#define ETXTBSY26
/* Text file busy */
#define EFBIG 27 /* File too large */
#define ENOSPC28
/* No space left on device */
#define ESPIPE29
/* Illegal seek */
#define EROFS 30 /* Read-only file system */
#define EMLINK31
/* Too many links */
#define EPIPE 32 /* Broken pipe */
#define EDOM 33 /* Math argument out of domain of func */
#define ERANGE34
/* Math result not representable */
#endif
头文件/usr/include/asm-generic/erno.h源码：
#ifndef _ASM_GENERIC_ERRNO_H
#define _ASM_GENERIC_ERRNO_H
#include <asm-generic/errno-base.h>
#define EDEADLK35
/* Resource deadlock would occur */
#define ENAMETOOLONG36
/* File name too long */
#define ENOLCK37
/* No record locks available */
#define ENOSYS38
/* Function not implemented */
#define ENOTEMPTY39
/* Directory not empty */
#define ELOOP 40 /* Too many symbolic links encountered */
#define EWOULDBLOCKEAGAIN
/* Operation would block */
#define ENOMSG42
/* No message of desired type */
#define EIDRM 43 /* Identifier removed */
#define ECHRNG44
/* Channel number out of range */
#define EL2NSYNC45
/* Level 2 not synchronized */
#define EL3HLT46
/* Level 3 halted */
#define EL3RST47
/* Level 3 reset */
#define ELNRNG48
/* Link number out of range */
#define EUNATCH49
/* Protocol driver not attached */
#define ENOCSI50
/* No CSI structure available */
#define EL2HLT51
/* Level 2 halted */
#define EBADE 52 /* Invalid exchange */
#define EBADR 53 /* Invalid request descriptor */
#define EXFULL54
/* Exchange full */
#define ENOANO55
/* No anode */
#define EBADRQC56
/* Invalid request code */
#define EBADSLT57
/* Invalid slot */
#define EDEADLOCKEDEADLK
#define EBFONT59
/* Bad font file format */
#define ENOSTR60
/* Device not a stream */
#define ENODATA61
/* No data available */
#define ETIME 62 /* Timer expired */
#define ENOSR 63 /* Out of streams resources */
#define ENONET64
/* Machine is not on the network */
#define ENOPKG65
/* Package not installed */
#define EREMOTE66
/* Object is remote */
#define ENOLINK67
/* Link has been severed */
#define EADV 68 /* Advertise error */
#define ESRMNT69
/* Srmount error */
#define ECOMM 70 /* Communication error on send */
#define EPROTO71
/* Protocol error */
#define EMULTIHOP72
/* Multihop attempted */
#define EDOTDOT73
/* RFS specific error */
#define EBADMSG74
/* Not a data message */
#define EOVERFLOW75
/* Value too large for defined data type */
#define ENOTUNIQ76
/* Name not unique on network */
#define EBADFD77
/* File descriptor in bad state */
#define EREMCHG78
/* Remote address changed */
#define ELIBACC79
/* Can not access a needed shared library */
#define ELIBBAD80
/* Accessing a corrupted shared library */
#define ELIBSCN81
/* .lib section in a.out corrupted */
#define ELIBMAX82
/* Attempting to link in too many shared libraries */
#define ELIBEXEC83
/* Cannot exec a shared library directly */
#define EILSEQ84
/* Illegal byte sequence */
#define ERESTART85
/* Interrupted system call should be restarted */
#define ESTRPIPE86
/* Streams pipe error */
#define EUSERS87
/* Too many users */
#define ENOTSOCK88
/* Socket operation on non-socket */
#define EDESTADDRREQ89
/* Destination address required */
#define EMSGSIZE90
/* Message too long */
#define EPROTOTYPE91
/* Protocol wrong type for socket */
#define ENOPROTOOPT92
/* Protocol not available */
#define EPROTONOSUPPORT93
/* Protocol not supported */
#define ESOCKTNOSUPPORT94
/* Socket type not supported */
#define EOPNOTSUPP95
/* Operation not supported on transport endpoint */
#define EPFNOSUPPORT96
/* Protocol family not supported */
#define EAFNOSUPPORT97
/* Address family not supported by protocol */
#define EADDRINUSE98
/* Address already in use */
#define EADDRNOTAVAIL99
/* Cannot assign requested address */
#define ENETDOWN100
/* Network is down */
#define ENETUNREACH101
/* Network is unreachable */
#define ENETRESET102
/* Network dropped connection because of reset */
#define ECONNABORTED103
/* Software caused connection abort */
#define ECONNRESET104
/* Connection reset by peer */
#define ENOBUFS105
/* No buffer space available */
#define EISCONN106
/* Transport endpoint is already connected */
#define ENOTCONN107
/* Transport endpoint is not connected */
#define ESHUTDOWN108
/* Cannot send after transport endpoint shutdown */
#define ETOOMANYREFS109
/* Too many references: cannot splice */
#define ETIMEDOUT110
/* Connection timed out */
#define ECONNREFUSED111
/* Connection refused */
#define EHOSTDOWN112
/* Host is down */
#define EHOSTUNREACH113
/* No route to host */
#define EALREADY114
/* Operation already in progress */
#define EINPROGRESS115
/* Operation now in progress */
#define ESTALE116
/* Stale NFS file handle */
#define EUCLEAN117
/* Structure needs cleaning */
#define ENOTNAM118
/* Not a XENIX named type file */
#define ENAVAIL119
/* No XENIX semaphores available */
#define EISNAM120
/* Is a named type file */
#define EREMOTEIO121
/* Remote I/O error */
#define EDQUOT122
/* Quota exceeded */
#define ENOMEDIUM123
/* No medium found */
#define EMEDIUMTYPE124
/* Wrong medium type */
#define ECANCELED125
/* Operation Canceled */
#define ENOKEY126
/* Required key not available */
#define EKEYEXPIRED127
/* Key has expired */
#define EKEYREVOKED128
/* Key has been revoked */
#define EKEYREJECTED129
/* Key was rejected by service */
/* for robust mutexes */
#define EOWNERDEAD130
/* Owner died */
#define ENOTRECOVERABLE131
/* State not recoverable */
#define ERFKILL 132/* Operation not possible due to RF-kill */
#endif