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The rmdir command remove directories, even if they are not empty.
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fdnsmxalist(1) [debian man page]

fdnsmxalist(1)						      General Commands Manual						    fdnsmxalist(1)

NAME
fdnsmxalist - resolve a list of MX records and their corresponding A records for hostname SYNOPSIS
fdnsmxalist [-x] <hostname> DESCRIPTION
fdnsmxalist will attempt to look up a list of MX records for hostname. If any are found, they are printed to standard output seperated by newlines in the format: Protocol (Priority) hostname:port The program then looks up lists of A and AAAA records for each MX record, and prints them to standard output, one IP per line. Lines are printed to standard output starting with "ERROR: " if any MX records have no corresponding A or AAAA records, are CNAMEs (an RFC viola- tion), or have A or AAAA records which point to non-routable IP addresses. If the -x switch is passed on the command line, the program outputs machine-parsable XML instead of the human-readable tree. Exit codes for the program are: 0 - Everything looks fine 1 - An MX has a non-routable IP 2 - An MX doesn't exist 3 - An MX is a CNAME 4 - An MX is an IP address 100 - Invalid syntax 103 - DNS timeout or host does not have MX records AUTHOR
Ian Gulliver <ian@penguinhosting.net> SEE ALSO
libfiredns(3) 2004-02-12 fdnsmxalist(1)

Check Out this Related Man Page

CHECKDNSRR(3)								 1							     CHECKDNSRR(3)

checkdnsrr - Check DNS records corresponding to a given Internet host name or IP address

SYNOPSIS
bool checkdnsrr (string $host, [string $type = "MX"]) DESCRIPTION
Searches DNS for records of type $type corresponding to $host. PARAMETERS
o $host -$host may either be the IP address in dotted-quad notation or the host name. o $type -$type may be any one of: A, MX, NS, SOA, PTR, CNAME, AAAA, A6, SRV, NAPTR, TXT or ANY. RETURN VALUES
Returns TRUE if any records are found; returns FALSE if no records were found or if an error occurred. CHANGELOG
+--------+---------------------------------------------------+ |Version | | | | | | | Description | | | | +--------+---------------------------------------------------+ | 5.3.0 | | | | | | | This function is now available on Windows plat- | | | forms. | | | | | 5.2.4 | | | | | | | TXT $type was added. | | | | +--------+---------------------------------------------------+ NOTES
Note For compatibility with Windows before this was implemented, then try the PEAR class Net_DNS. SEE ALSO
dns_get_record(3), getmxrr(3), gethostbyaddr(3), gethostbyname(3), gethostbynamel(3), the named(8) manual page. PHP Documentation Group CHECKDNSRR(3)

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