|-c||Changes the default root directory of a connecting host via chroot(2) based on the connecting IP address. This prevents multiple clients from writing to the same file at the same time. If the directory does not exist, the client connection is refused. The -s option is required for -c and the specified directory is used as a base.|
|-C||Operates the same as -c except it falls back to directory specified via -s if a directory does not exist for the clients IP.|
|-F||Use this strftime(3) compatible format string for the creation of the suffix if -W is specified. By default the string "%Y%m%d" is used.|
|-d, -d [value]|
Enables debug output.
is not specified, then the debug level is increased by one
for each instance of
which is specified.
If value is specified, then the debug level is set to value. The debug level is a bitmask implemented in src/libexec/tftpd/tftp-utils.h. Valid values are 0 (DEBUG_NONE), 1 (DEBUG_PACKETS), 2, (DEBUG_SIMPLE), 4 (DEBUG_OPTIONS), and 8 (DEBUG_ACCESS). Multiple debug values can be combined in the bitmask by logically ORing the values. For example, specifying -d 15 will enable all the debug values.
|-l||Log all requests using syslog(3) with the facility of LOG_FTP. Note: Logging of LOG_FTP messages must also be enabled in the syslog configuration file, syslog.conf(5).|
|-n||Suppress negative acknowledgement of requests for nonexistent relative filenames.|
|-o||Disable support for RFC2347 style TFTP Options.|
|Cause tftpd to change its root directory to directory. After doing that but before accepting commands, tftpd will switch credentials to an unprivileged user.|
|Switch credentials to user (default "nobody") when the -s option is used. The user must be specified by name, not a numeric UID.|
|Set the umask for newly created files. The default is 022 (S_IWGRP | S_IWOTH).|
|-w||Allow write requests to create new files. By default tftpd requires that the file specified in a write request exist. Note that this only works in directories writable by the user specified with -u option|
|-W||As -w but append a YYYYMMDD.nn sequence number to the end of the filename. Note that the string YYYYMMDD can be changed with the -F option.|
tftp(1), chroot(2), syslog(3), inetd.conf(5), services(5), syslog.conf(5), inetd(8)
The following RFCs are supported:
.Rs RFC 1350: The TFTP Protocol (Revision 2)
.Rs RFC 2347: TFTP Option Extension
.Rs RFC 2348: TFTP Blocksize Option
.Rs RFC 2349: TFTP Timeout Interval and Transfer Size Options
The non-standard rollover and blksize2 TFTP options are mentioned here:
.Rs Extending TFTP
The tftpd utility appeared in BSD 4.2 ; the -s option was introduced in
.Fx 2.2 , the -u option was introduced in
.Fx 4.2 , the -c option was introduced in
.Fx 4.3 , and the -F and -W options were introduced in
.Fx 7.4 .
Support for Timeout Interval and Transfer Size Options (RFC2349) was introduced in
.Fx 5.0 , support for the TFTP Blocksize Option (RFC2348) and the blksize2 option was introduced in
.Fx 7.4 .
Files larger than 33,553,919 octets (65535 blocks, last one <512 octets) cannot be correctly transferred without client and server supporting blocksize negotiation (RFCs 2347 and 2348), or the non-standard TFTP rollover option. As a kludge, tftpd accepts a sequence of block number which wrap to zero after 65535, even if the rollover option is not specified.
Many tftp clients will not transfer files over 16,776,703 octets (32767 blocks), as they incorrectly count the block number using a signed rather than unsigned 16-bit integer.