NAME

fdtar− tape archiver for fast-disk

SYNOPSIS

fdtar [ key ] [ name ... ]

DESCRIPTION

Fdtar saves and restores multiple Fast-Disk files and directories on a single file (usually a magnetic tape, but it can be any file).  Fdtar’s actions are controlled by the key argument.  The key is a string of characters containing at most one function letter and possibly one or more function modifiers.  Other arguments to fdtar are file or directory names specifying which files to dump or restore.  In all cases, appearance of a directory name refers to the files and (recursively) subdirectories of that directory. 

Archives written by fdtar can be read by the UNIX utility tar, and vice versa.

The function portion of the key is specified by one of the following letters:

r The named files are written on the end of the tape.  The c function implies this. 

x The named files are extracted from the tape.  If the named file matches a directory whose contents had been written onto the tape, this directory is (recursively) extracted.  The owner, modification time, and mode are restored (if possible).  If no file argument is given, the entire content of the tape is extracted.  Note that if multiple entries specifying the same file are on the tape, the last one overwrites all earlier. 

t The names of the specified files are listed each time they occur on the tape.  If no file argument is given, all of the names on the tape are listed. 

u The named files are added to the tape if either they are not already there or have been modified since last put on the tape. 

c Create a new tape; writing begins on the beginning of the tape instead of after the last file.  This command implies r. 

The following characters may be used in addition to the letter which selects the function desired. 

0, ..., 9 This modifier selects an alternate drive on which the tape is mounted.  The default is drive 0 at 1600 bpi, which is normally /dev/rmt8. 

v Normally fdtar does its work silently.  The v (verbose) option directs fdtar to print the name of each file it treats preceded by the function letter.  With the t function, the verbose option gives more information about the tape entries than just their names. 

w Fdtar prints the action to be taken followed by file name, then wait for user confirmation. If a word beginning with ‘y’ is given, the action is done. Any other input means don’t do it. 

f Fdtar uses the next argument as the name of the archive instead of /dev/rmt?. If the name of the file is ‘−’, fdtar writes to standard output or reads from standard input, whichever is appropriate. Thus, fdtar can be used as the head or tail of a filter chain.  Fdtar can also be used in a pipeline with tar(1) to move hierarchies between the Fast-Disk and the UNIX filesystems, for example:

cd unixdir; tar cf - . | (fdtar xf -)

b Fdtar uses the next argument as the blocking factor for tape records. The default is 20 (the maximum). This option should only be used with raw magnetic tape archives (See f above).  The block size is determined automatically when reading tapes (key letters x and t). 

m directs fdtar not to restore the modification times.  The modification time will be the time of extraction. 

i Normally, when fdtar encounters a bad file header block on the tape, it complains and exits.  The i option instructs fdtar to persist in trying to locate a valid file header instead of exiting. 

B Forces input and output blocking to 20 blocks per record.  This option is available so that fdtar can work across a communications channel where the blocking may not be maintained. 

C If a file name is preceded by −C, then fdtar will perform a fd_chdir(3H) to that file name.  This allows multiple directories not related by a close common parent to be archived using short relative path names.  For example, to archive files from /abc/def and from /xyz, one might use the command

fdtar c -C /abc def -C / xyz

FILES

/dev/rmt? 
/dev/rmx∗
/tmp/tar∗

SEE ALSO

tar(1), libfd(3H), fd_chdir(3H), tar(5)

DIAGNOSTICS

Complaints about bad key characters and tape read/write errors. 

Complaints about "directory checksum error", reflecting indecipherable file header data in archive being extracted or listed. 

Complaints when trying to restore a symbolic link from a tape written by tar; no file is restored in this case.

When trying to restore a hard link from a tape written by tar, fdtar reports this and makes a second copy of the contents of the file under the new name. 

BUGS

There is no way to ask for the n-th occurrence of a file.
Tape errors are handled ungracefully.
The u option can be slow. 
The current limit on file name length is 100 characters.
When extracting tapes created with the r or u options, directory modification times may not be set correctly. 

Release β  —  Last change: 10/12/88