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postmap - Unix, Linux Command


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NAME

postmap - Postfix lookup table management

SYNOPSIS

postmap [-Nfinoprsvw] [-c config_dir] [-d key] [-q key]
[file_type:]file_name ...

DESCRIPTION

The postmap(1) command creates or queries one or more Postfix lookup tables, or updates an existing one. The input and output file formats are expected to be compatible with:

   makemap file_type file_name < file_name

If the result files do not exist they will be created with the same group and other read permissions as the source file.

While the table update is in progress, signal delivery is postponed, and an exclusive, advisory, lock is placed on the entire table, in order to avoid surprises in spectator programs.

INPUT FILE FORMAT


The format of a lookup table input file is as follows:
TagDescription
o A table entry has the form

   key whitespace value

o Empty lines and whitespace-only lines are ignored, as are lines whose first non-whitespace character is a ‘#’.
o A logical line starts with non-whitespace text. A line that starts with whitespace continues a logical line.
The key and value are processed as is, except that surrounding white space is stripped off. Unlike with Postfix alias databases, quotes cannot be used to protect lookup keys that contain special characters such as ‘#’ or whitespace.

By default the lookup key is mapped to lowercase to make the lookups case insensitive; as of Postfix 2.3 this case folding happens only with tables whose lookup keys are fixed-case strings such as btree:, dbm: or hash:. With earlier versions, the lookup key is folded even with tables where a lookup field can match both upper and lower case text, such as regexp: and pcre:. This resulted in loss of information with $number substitutions.

COMMAND-LINE ARGUMENTS


TagDescription
-c config_dir Read the main.cf configuration file in the named directory instead of the default configuration directory.
-d key Search the specified maps for key and remove one entry per map. The exit status is zero when the requested information was found.

If a key value of - is specified, the program reads key values from the standard input stream. The exit status is zero when at least one of the requested keys was found.

-f Do not fold the lookup key to lower case while creating or querying a table.
-i Incremental mode. Read entries from standard input and do not truncate an existing database. By default, postmap(1) creates a new database from the entries in file_name.
-N Include the terminating null character that terminates lookup keys and values. By default, postmap(1) does whatever is the default for the host operating system.
-n Don’t include the terminating null character that terminates lookup keys and values. By default, postmap(1) does whatever is the default for the host operating system.
-o Do not release root privileges when processing a non-root input file. By default, postmap(1) drops root privileges and runs as the source file owner instead.
-p Do not inherit the file access permissions from the input file when creating a new file. Instead, create a new file with default access permissions (mode 0644).
-q key Search the specified maps for key and write the first value found to the standard output stream. The exit status is zero when the requested information was found.

If a key value of - is specified, the program reads key values from the standard input stream and writes one line of key value output for each key that was found. The exit status is zero when at least one of the requested keys was found.

-r When updating a table, do not complain about attempts to update existing entries, and make those updates anyway.
-s Retrieve all database elements, and write one line of key value output for each element. The elements are printed in database order, which is not necessarily the same as the original input order. This feature is available in Postfix version 2.2 and later, and is not available for all database types.
-v Enable verbose logging for debugging purposes. Multiple -v options make the software increasingly verbose.
-w When updating a table, do not complain about attempts to update existing entries, and ignore those attempts.
Arguments:
file_type The database type. To find out what types are supported, use the "postconf -m" command.

The postmap(1) command can query any supported file type, but it can create only the following file types:

TagDescription
btree The output file is a btree file, named file_name.db. This is available on systems with support for db databases.
cdb The output consists of one file, named file_name.cdb. This is available on systems with support for cdb databases.
dbm The output consists of two files, named file_name.pag and file_name.dir. This is available on systems with support for dbm databases.
hash The output file is a hashed file, named file_name.db. This is available on systems with support for db databases.
sdbm The output consists of two files, named file_name.pag and file_name.dir. This is available on systems with support for sdbm databases.
When no file_type is specified, the software uses the database type specified via the default_database_type configuration parameter.
file_name The name of the lookup table source file when rebuilding a database.

DIAGNOSTICS

Problems are logged to the standard error stream and to syslogd(8). No output means that no problems were detected. Duplicate entries are skipped and are flagged with a warning.

postmap(1) terminates with zero exit status in case of success (including successful "postmap -q" lookup) and terminates with non-zero exit status in case of failure.

ENVIRONMENT


TagDescription
MAIL_CONFIG Directory with Postfix configuration files.
MAIL_VERBOSE Enable verbose logging for debugging purposes.

CONFIGURATION PARAMETERS


The following main.cf parameters are especially relevant to this program. The text below provides only a parameter summary. See postconf(5) for more details including examples.
TagDescription
berkeley_db_create_buffer_size (16777216) The per-table I/O buffer size for programs that create Berkeley DB hash or btree tables.
berkeley_db_read_buffer_size (131072) The per-table I/O buffer size for programs that read Berkeley DB hash or btree tables.
config_directory (see ’postconf -d’ output) The default location of the Postfix main.cf and master.cf configuration files.
default_database_type (see ’postconf -d’ output) The default database type for use in newaliases(1), postalias(1) and postmap(1) commands.
syslog_facility (mail) The syslog facility of Postfix logging.
syslog_name (postfix) The mail system name that is prepended to the process name in syslog records, so that "smtpd" becomes, for example, "postfix/smtpd".

SEE ALSO

postalias(1), create/update/query alias database
postconf(1), supported database types
postconf(5), configuration parameters
syslogd(8), system logging

README FILES


Use "postconf readme_directory" or "postconf html_directory" to locate this information.
DATABASE_README, Postfix lookup table overview

LICENSE


The Secure Mailer license must be distributed with this software.

AUTHOR(S)

Wietse Venema
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA


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