| EPERM | 1 | Fourth Edition Unix | 1973-11 |
| ENOENT | 2 | Fourth Edition Unix | 1973-11 |
| ESRCH | 3 | Fourth Edition Unix | 1973-11 |
| EINTR | 4 | Sixth Edition Unix | 1975-05 |
| EIO | 5 | Fourth Edition Unix | 1973-11 |
| ENXIO | 6 | Fourth Edition Unix | 1973-11 |
| ENOEXEC | 8 | Fourth Edition Unix | 1973-11 |
| EBADF | 9 | Fourth Edition Unix | 1973-11 |
| ECHILD | 10 | Fourth Edition Unix | 1973-11 |
| EAGAIN | 11 | Fourth Edition Unix | 1973-11 |
| ENOMEM | 12 | Fourth Edition Unix | 1973-11 |
| EACCES | 13 | Fourth Edition Unix | 1973-11 |
| EFAULT | 14 (was 106) | Fourth Edition Unix | 1973-11 |
| ENOTBLK | 15 | Fourth Edition Unix | 1973-11 |
| EBUSY | 16 | Fourth Edition Unix | 1973-11 |
| EEXIST | 17 | Fourth Edition Unix | 1973-11 |
| EXDEV | 18 | Fourth Edition Unix | 1973-11 |
| ENODEV | 19 | Fourth Edition Unix | 1973-11 |
| ENOTDIR | 20 | Fourth Edition Unix | 1973-11 |
| EISDIR | 21 | Fourth Edition Unix | 1973-11 |
| EINVAL | 22 | Fourth Edition Unix | 1973-11 |
| ENFILE | 23 | Fourth Edition Unix | 1973-11 |
| EMFILE | 24 | Fourth Edition Unix | 1973-11 |
| ENOTTY | 25 | Fourth Edition Unix | 1973-11 |
| ETXTBSY | 26 | Fourth Edition Unix | 1973-11 |
| EFBIG | 27 | Fourth Edition Unix | 1973-11 |
| ENOSPC | 28 | Fourth Edition Unix | 1973-11 |
| ESPIPE | 29 | Fifth Edition Unix | 1974-06 |
| EROFS | 30 | Fifth Edition Unix | 1974-06 |
| EMLINK | 31 | Fifth Edition Unix | 1974-06 |
| EPIPE | 32 | Sixth Edition Unix | 1975-05 |
| EDOM | 33 | Seventh Edition Unix | 1979-01 |
| ERANGE | 34 | Seventh Edition Unix | 1979-01 |
| EDEADLK | 35 (was 45) | System V release 1 | 1983-01 |
| ENAMETOOLONG | 36 (was 63) | 4.1c BSD | 1982-12 |
| ENOLCK | 37 (was 46) | System V release 1 | 1983-01 |
| ENOSYS | 38 (was 89) | System V release 1 | 1983-01 |
| ENOTEMPTY | 39 (was 66) | 4.1c BSD | 1982-12 |
| ELOOP | 40 (was 62) | 4.1c BSD | 1982-12 |
| EWOULDBLOCK | 11 (was 35) | 4.1c BSD | 1982-12 |
| ENOMSG | 42 (was 35) | System V release 1 | 1983-01 |
| EIDRM | 43 (was 36) | System V release 1 | 1983-01 |
| ECHRNG | 44 (was 37) | System V release 1 | 1983-01 |
| ELNRNG | 48 (was 41) | System V release 1 | 1983-01 |
| EUNATCH | 49 (was 42) | System V release 1 | 1983-01 |
| ENOCSI | 50 (was 43) | System V release 1 | 1983-01 |
| EBADE | 52 (was 50) | System V release 1 | 1983-01 |
| EBADR | 53 (was 51) | System V release 1 | 1983-01 |
| EXFULL | 54 (was 52) | System V release 1 | 1983-01 |
| ENOANO | 55 (was 53) | System V release 1 | 1983-01 |
| EBADRQC | 56 (was 54) | System V release 1 | 1983-01 |
| EBADSLT | 57 (was 55) | System V release 1 | 1983-01 |
| EDEADLOCK | 35 (was 56) | System V release 1 | 1983-01 |
| EBFONT | 59 (was 57) | System V release 1 | 1983-01 |
| ENOSTR | 60 | System V release 1 | 1983-01 |
| ENODATA | 61 | System V release 1 | 1983-01 |
| ETIME | 62 | System V release 1 | 1983-01 |
| ENOSR | 63 | System V release 1 | 1983-01 |
| ENONET | 64 | System V release 1 | 1983-01 |
| ENOPKG | 65 | System V release 1 | 1983-01 |
| EREMOTE | 66 | System V release 1 | 1983-01 |
| ENOLINK | 67 | System V release 1 | 1983-01 |
| EADV | 68 | System V release 1 | 1983-01 |
| ESRMNT | 69 | System V release 1 | 1983-01 |
| ECOMM | 70 | System V release 1 | 1983-01 |
| EPROTO | 71 | System V release 1 | 1983-01 |
| EMULTIHOP | 72 (was 74) | System V release 1 | 1983-01 |
| EDOTDOT | 73 | Linux 2.6.33.2 | 2010-04 |
| EBADMSG | 74 (was 77) | System V release 1 | 1983-01 |
| EOVERFLOW | 75 (was 79) | System V release 1 | 1983-01 |
| ENOTUNIQ | 76 (was 80) | System V release 1 | 1983-01 |
| EBADFD | 77 (was 81) | System V release 1 | 1983-01 |
| EREMCHG | 78 (was 82) | System V release 1 | 1983-01 |
| ELIBACC | 79 (was 83) | System V release 1 | 1983-01 |
| ELIBBAD | 80 (was 84) | System V release 1 | 1983-01 |
| ELIBSCN | 81 (was 85) | System V release 1 | 1983-01 |
| ELIBMAX | 82 (was 86) | System V release 1 | 1983-01 |
| ELIBEXEC | 83 (was 87) | System V release 1 | 1983-01 |
| EILSEQ | 84 (was 88) | System V release 1 | 1983-01 |
| ERESTART | 85 (was 91) | System V release 1 | 1983-01 |
| ESTRPIPE | 86 (was 92) | System V release 1 | 1983-01 |
| EUSERS | 87 (was 68) | 4.1c BSD | 1982-12 |
| ENOTSOCK | 88 (was 38) | 4.1c BSD | 1982-12 |
| EDESTADDRREQ | 89 (was 39) | 4.1c BSD | 1982-12 |
| EMSGSIZE | 90 (was 40) | 4.1c BSD | 1982-12 |
| EPROTOTYPE | 91 (was 41) | 4.1c BSD | 1982-12 |
| ENOPROTOOPT | 92 (was 42) | 4.1c BSD | 1982-12 |
| EPROTONOSUPPORT | 93 (was 43) | 4.1c BSD | 1982-12 |
| ESOCKTNOSUPPORT | 94 (was 44) | 4.1c BSD | 1982-12 |
| EOPNOTSUPP | 95 (was 45) | 4.1c BSD | 1982-12 |
| EPFNOSUPPORT | 96 (was 46) | 4.1c BSD | 1982-12 |
| EAFNOSUPPORT | 97 (was 47) | 4.1c BSD | 1982-12 |
| EADDRINUSE | 98 (was 48) | 4.1c BSD | 1982-12 |
| EADDRNOTAVAIL | 99 (was 49) | 4.1c BSD | 1982-12 |
| ENETDOWN | 100 (was 50) | 4.1c BSD | 1982-12 |
| ENETUNREACH | 101 (was 51) | 4.1c BSD | 1982-12 |
| ENETRESET | 102 (was 52) | 4.1c BSD | 1982-12 |
| ECONNABORTED | 103 (was 53) | 4.1c BSD | 1982-12 |
| ECONNRESET | 104 (was 54) | 4.1c BSD | 1982-12 |
| ENOBUFS | 105 (was 55) | 4.1c BSD | 1982-12 |
| EISCONN | 106 (was 56) | 4.1c BSD | 1982-12 |
| ENOTCONN | 107 (was 57) | 4.1c BSD | 1982-12 |
| ESHUTDOWN | 108 (was 58) | 4.1c BSD | 1982-12 |
| ETOOMANYREFS | 109 (was 59) | 4.1c BSD | 1982-12 |
| ETIMEDOUT | 110 (was 60) | 4.1c BSD | 1982-12 |
| ECONNREFUSED | 111 (was 61) | 4.1c BSD | 1982-12 |
| EHOSTDOWN | 112 (was 64) | 4.1c BSD | 1982-12 |
| EHOSTUNREACH | 113 (was 65) | 4.1c BSD | 1982-12 |
| EALREADY | 114 (was 37) | 4.1c BSD | 1982-12 |
| EINPROGRESS | 115 (was 36) | 4.1c BSD | 1982-12 |
| ESTALE | 116 (was 151) | System V release 1 | 1983-01 |
| EUCLEAN | 117 (was 135) | System V release 1 | 1983-01 |
| ENOTNAM | 118 (was 137) | System V release 1 | 1983-01 |
| ENAVAIL | 119 (was 138) | System V release 1 | 1983-01 |
| EISNAM | 120 (was 139) | System V release 1 | 1983-01 |
| EREMOTEIO | 121 (was 140) | System V release 1 | 1983-01 |
| EDQUOT | 122 (was 69) | 4.1c BSD | 1982-12 |
| ENOMEDIUM | 123 (was 85) | OpenBSD 4.6 | 2009-10 |
| EMEDIUMTYPE | 124 (was 86) | OpenBSD 4.6 | 2009-10 |
| ECANCELED | 125 (was 85) | FreeBSD 5.3 | 2004-08 |
| ENOKEY | 126 | Linux 2.6.33.2 | 2010-04 |
| EKEYEXPIRED | 127 | Linux 2.6.33.2 | 2010-04 |
| EKEYREVOKED | 128 | Linux 2.6.33.2 | 2010-04 |
| EKEYREJECTED | 129 | Linux 2.6.33.2 | 2010-04 |
| EOWNERDEAD | 130 (was 58) | OpenSolaris build 135 | 2010-03 |
| ENOTRECOVERABLE | 131 (was 59) | OpenSolaris build 135 | 2010-03 |
| ERFKILL | 132 | Linux 2.6.33.2 | 2010-04 |