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10911 dd: add input flag fullblock

@@ -1,47 +1,41 @@
 DD(1M)                       Maintenance Commands                       DD(1M)
 
-
-
 NAME
        dd - convert and copy a file
 
 SYNOPSIS
-       /usr/bin/dd [operand=value]...
+     /usr/bin/dd [operand=value] ...
 
-
 DESCRIPTION
        The dd utility copies the specified input file to the specified output
        with possible conversions. The standard input and output are used by
        default.  The input and output block sizes may be specified to take
        advantage of raw physical I/O. Sizes are specified in bytes; a number
        may end with k, b, or w to specify multiplication by 1024, 512, or 2,
        respectively.  Numbers may also be separated by x to indicate
        multiplication.
 
-
        The dd utility reads the input one block at a time, using the specified
-       input block size. dd then processes the block of data actually
-       returned, which could be smaller than the requested block size. dd
-       applies any conversions that have been specified and writes the
-       resulting data to the output in blocks of the specified output block
-       size.
+     input block size.  dd then processes the block of data actually returned,
+     which could be smaller than the requested block size unless the input
+     flag fullblock is used.  dd applies any conversions that have been
+     specified and writes the resulting data to the output in blocks of the
+     specified output block size.
 
-
        cbs is used only if ascii, asciib, unblock, ebcdic, ebcdicb, ibm, ibmb,
-       or block conversion is specified. In the first two cases, cbs
-       characters are copied into the conversion buffer, any specified
-       character mapping is done, trailing blanks are trimmed, and a NEWLINE
-       is added before sending the line to output. In the last three cases,
-       characters up to NEWLINE are read into the conversion buffer and blanks
-       are added to make up an output record of size cbs.  ASCII files are
-       presumed to contain NEWLINE characters. If cbs is unspecified or 0, the
-       ascii, asciib, ebcdic, ebcdicb, ibm, and ibmb options convert the
-       character set without changing the input file's block structure. The
-       unblock and block options become a simple file copy.
+     or block conversion is specified.  In the first two cases, cbs characters
+     are copied into the conversion buffer, any specified character mapping is
+     done, trailing blanks are trimmed, and a NEWLINE is added before sending
+     the line to output.  In the last three cases, characters up to NEWLINE
+     are read into the conversion buffer and blanks are added to make up an
+     output record of size cbs.  ASCII files are presumed to contain NEWLINE
+     characters.  If cbs is unspecified or 0, the ascii, asciib, ebcdic,
+     ebcdicb, ibm, and ibmb options convert the character set without changing
+     the input file's block structure.  The unblock and block options become a
+     simple file copy.
 
-
        After completion, dd reports the number of whole and partial input and
        output blocks.
 
 OPERANDS
        The following operands are supported:

@@ -48,254 +42,215 @@
 
        if=file
 
            Specifies the input path. Standard input is the default.
 
-
        of=file
 
-           Specifies the output path. Standard output is the default. If the
-           seek=expr conversion is not also specified, the output file will be
-           truncated before the copy begins, unless conv=notrunc is specified.
-           If seek=expr is specified, but conv=notrunc is not, the effect of
-           the copy will be to preserve the blocks in the output file over
-           which dd seeks, but no other portion of the output file will be
-           preserved. (If the size of the seek plus the size of the input file
-           is less than the previous size of the output file, the output file
-           is shortened by the copy.)
+             Specifies the output path.  Standard output is the default.  If
+             the seek=expr conversion is not also specified, the output file
+             will be truncated before the copy begins, unless conv=notrunc is
+             specified.  If seek=expr is specified, but conv=notrunc is not,
+             the effect of the copy will be to preserve the blocks in the
+             output file over which dd seeks, but no other portion of the
+             output file will be preserved.  (If the size of the seek plus the
+             size of the input file is less than the previous size of the
+             output file, the output file is shortened by the copy.)
 
-
        ibs=n
 
            Specifies the input block size in n bytes (default is 512).
 
-
        obs=n
 
            Specifies the output block size in n bytes (default is 512).
 
-
        bs=n
 
-           Sets both input and output block sizes to n bytes, superseding ibs=
-           and obs=. If no conversion other than sync, noerror, and notrunc is
-           specified, each input block is copied to the output as a single
-           block without aggregating short blocks.
+             Sets both input and output block sizes to n bytes, superseding
+             ibs= and obs=.  If no conversion other than sync, noerror, and
+             notrunc is specified, each input block is copied to the output as
+             a single block without aggregating short blocks.
 
-
        cbs=n
 
-           Specifies the conversion block size for block and unblock in bytes
-           by n (default is 0). If cbs= is omitted or given a value of 0,
-           using block or unblock produces unspecified results.
+             Specifies the conversion block size for block and unblock in
+             bytes by n (default is 0). If cbs= is omitted or given a value of
+             0, using block or unblock produces unspecified results.
 
            This option is used only if ASCII or EBCDIC conversion is
-           specified. For the ascii and asciib operands, the input is handled
-           as described for the unblock operand except that characters are
-           converted to ASCII before the trailing SPACE characters are
-           deleted. For the ebcdic, ebcdicb, ibm, and ibmb operands, the input
-           is handled as described for the block operand except that the
-           characters are converted to EBCDIC or IBM EBCDIC after the trailing
-           SPACE characters are added.
+             specified.  For the ascii and asciib operands, the input is
+             handled as described for the unblock operand except that
+             characters are converted to ASCII before the trailing SPACE
+             characters are deleted.  For the ebcdic, ebcdicb, ibm, and ibmb
+             operands, the input is handled as described for the block operand
+             except that the characters are converted to EBCDIC or IBM EBCDIC
+             after the trailing SPACE characters are added.
 
-
        files=n
 
            Copies and concatenates n input files before terminating (makes
            sense only where input is a magnetic tape or similar device).
 
-
        skip=n
 
-           Skips n input blocks (using the specified input block size) before
-           starting to copy. On seekable files, the implementation reads the
-           blocks or seeks past them. On non-seekable files, the blocks are
-           read and the data is discarded.
+             Skips n input blocks (using the specified input block size)
+             before starting to copy.  On seekable files, the implementation
+             reads the blocks or seeks past them.  On non-seekable files, the
+             blocks are read and the data is discarded.
 
-
        iseek=n
 
            Seeks n blocks from beginning of input file before copying
            (appropriate for disk files, where skip can be incredibly slow).
 
-
        oseek=n
 
            Seeks n blocks from beginning of output file before copying.
 
-
        seek=n
 
            Skips n blocks (using the specified output block size) from
            beginning of output file before copying. On non-seekable files,
-           existing blocks are read and space from the current end-of-file to
-           the specified offset, if any, is filled with null bytes. On
-           seekable files, the implementation seeks to the specified offset or
-           reads the blocks as described for non-seekable files.
+             existing blocks are read and space from the current end-of-file
+             to the specified offset, if any, is filled with null bytes.  On
+             seekable files, the implementation seeks to the specified offset
+             or reads the blocks as described for non-seekable files.
 
-
        ostride=n
 
-           Writes every nth block (using the specified output block size) when
-           writing output.  Skips n - 1 blocks after writing each record.
+             Writes every nth block (using the specified output block size)
+             when writing output.  Skips n - 1 blocks after writing each
+             record.
 
-
        istride=n
 
            Reads every nth block (using the specified input block size) when
            reading input.  Skips n - 1 blocks after reading each record.
 
-
        stride=n
 
            Reads every nth block (using the specified input block size) when
-           reading input.  Skips n - 1 blocks after reading each record.  Also
-           writes every nth block (using the specified output block size) when
-           writing output.  Skips n - 1 blocks after writing each record.
+             reading input.  Skips n - 1 blocks after reading each record.
+             Also writes every nth block (using the specified output block
+             size) when writing output.  Skips n - 1 blocks after writing each
+             record.
 
-
        count=n
 
            Copies only n input blocks.
 
-
        conv=value[,value...]
 
            Where values are comma-separated symbols from the following list:
 
-           ascii
-                      Converts EBCDIC to ASCII.
+             ascii   Converts EBCDIC to ASCII.
 
 
-           asciib
-                      Converts EBCDIC to ASCII using BSD-compatible character
+             asciib  Converts EBCDIC to ASCII using BSD-compatible character
                       translations.
 
-
-           ebcdic
-                      Converts ASCII to EBCDIC. If converting fixed-length
+             ebcdic  Converts ASCII to EBCDIC.  If converting fixed-length
                       ASCII records without NEWLINEs, sets up a pipeline with
                       dd conv=unblock beforehand.
 
-
-           ebcdicb
-                      Converts ASCII to EBCDIC using BSD-compatible character
+             ebcdicb Converts ASCII to EBCDIC using BSD-compatible character
                       translations. If converting fixed-length ASCII records
-                      without NEWLINEs, sets up a pipeline with dd
-                      conv=unblock beforehand.
+                     without NEWLINEs, sets up a pipeline with dd conv=unblock
+                     beforehand.
 
-
-           ibm
-                      Slightly different map of ASCII to EBCDIC. If converting
+             ibm     Slightly different map of ASCII to EBCDIC.  If converting
                       fixed-length ASCII records without NEWLINEs, sets up a
                       pipeline with dd conv=unblock beforehand.
 
-
-           ibmb
-                      Slightly different map of ASCII to EBCDIC using
+             ibmb    Slightly different map of ASCII to EBCDIC using
                       BSD-compatible character translations. If converting
                       fixed-length ASCII records without NEWLINEs, sets up a
                       pipeline with dd conv=unblock beforehand.
 
-           The ascii (or asciib), ebcdic (or ebcdicb), and ibm (or ibmb)
+             The ascii (or asciib ), ebcdic (or ebcdicb ), and ibm (or ibmb)
            values are mutually exclusive.
 
-           block
-                      Treats the input as a sequence of NEWLINE-terminated or
-                      EOF-terminated variable-length records independent of
-                      the input block boundaries. Each record is converted to
-                      a record with a fixed length specified by the conversion
+             block   Treats the input as a sequence of NEWLINE-terminated or
+                     EOF-terminated variable-length records independent of the
+                     input block boundaries.  Each record is converted to a
+                     record with a fixed length specified by the conversion
                       block size. Any NEWLINE character is removed from the
                       input line. SPACE characters are appended to lines that
                       are shorter than their conversion block size to fill the
                       block. Lines that are longer than the conversion block
                       size are truncated to the largest number of characters
                       that will fit into that size. The number of truncated
                       lines is reported.
 
-
-           unblock
-                      Converts fixed-length records to variable length. Reads
+             unblock Converts fixed-length records to variable length.  Reads
                       a number of bytes equal to the conversion block size (or
                       the number of bytes remaining in the input, if less than
                       the conversion block size), delete all trailing SPACE
                       characters, and append a NEWLINE character.
 
            The  block and unblock values are mutually exclusive.
 
-           lcase
-                    Maps upper-case characters specified by the LC_CTYPE
-                    keyword tolower to the corresponding lower-case character.
-                    Characters for which no mapping is specified are not
-                    modified by this conversion.
+             lcase   Maps upper-case characters specified by the LC_CTYPE
+                     keyword tolower to the corresponding lower-case
+                     character.  Characters for which no mapping is specified
+                     are not modified by this conversion.
 
+             ucase   Maps lower-case characters specified by the LC_CTYPE
+                     keyword toupper to the corresponding upper-case
+                     character.  Characters for which no mapping is specified
+                     are not modified by this conversion.
 
-           ucase
-                    Maps lower-case characters specified by the LC_CTYPE
-                    keyword toupper to the corresponding upper-case character.
-                    Characters for which no mapping is specified are not
-                    modified by this conversion.
-
            The lcase and ucase symbols are mutually exclusive.
 
-           swab
-                      Swaps every pair of input bytes. If the current input
+             swab    Swaps every pair of input bytes.  If the current input
                       record is an odd number of bytes, the last byte in the
                       input record is ignored.
 
-
-           noerror
-                      Does not stop processing on an input error. When an
+             noerror Does not stop processing on an input error.  When an
                       input error occurs, a diagnostic message is written on
                       standard error, followed by the current input and output
                       block counts in the same format as used at completion.
-                      If the sync conversion is specified, the missing input
-                      is replaced with null bytes and processed normally.
+                     If the sync conversion is specified, the missing input is
+                     replaced with null bytes and processed normally.
                       Otherwise, the input block will be omitted from the
                       output.
 
+             notrunc Does not truncate the output file.  Preserves blocks in
+                     the output file not explicitly written by this invocation
+                     of dd.  (See also the preceding of=file operand.)
 
-           notrunc
-                      Does not truncate the output file. Preserves blocks in
-                      the output file not explicitly written by this
-                      invocation of dd. (See also the preceding of=file
-                      operand.)
-
-
-           sync
-                      Pads every input block to the size of the ibs= buffer,
+             sync    Pads every input block to the size of the ibs= buffer,
                       appending null bytes. (If either block or unblock is
                       also specified, appends SPACE characters, rather than
                       null bytes.)
 
+     iflag=value[,value ...]
 
+             Where values are comma-separated symbols from the following list
+             which affect the behavior of reading from the input file:
 
-       oflag=value[,value...]
+             fullblock Accumulate full blocks of input.
 
-       Where values are comma-separated symbols from the following list which
-       affect the behavior of writing the output file:
+     oflag=value[,value ...]
 
-       dsync
-                  The output file is opened with the O_DSYNC flag set. All
+             Where values are comma-separated symbols from the following list
+             which affect the behavior of writing the output file:
+
+             dsync   The output file is opened with the O_DSYNC flag set.  All
                   data writes will be synchronous. For more information on
                   O_DSYNC see fcntl.h(3HEAD).
 
-
-       sync
-                  The output file is opened with the O_SYNC flag set. All data
-                  and metadata writes will be synchronous. For more
+             sync    The output file is opened with the O_SYNC.  All data and
+                     metadata writes will be synchronous.  For more
                   information on O_SYNC see fcntl.h(3HEAD).
 
+     If operands other than conv= and oflag= are specified more than once, the
+     last specified operand=value is used.
 
-
-       If operands other than conv= and oflag= are specified more than once,
-       the last specified operand=value is used.
-
-
        For the bs=, cbs=, ibs=, and obs= operands, the application must supply
        an expression specifying a size in bytes. The expression, expr, can be:
-
            1.     a positive decimal number
 
            2.     a positive decimal number followed by k, specifying
                   multiplication by 1024
 

@@ -318,15 +273,14 @@
                   multiplication by 1024*1024*1024*1024*1024*1024*1024
 
            9.     a positive decimal number followed by b, specifying
                   multiplication by 512
 
-           10.    two or more positive decimal numbers (with or without k or
-                  b) separated by x, specifying the product of the indicated
+           10.  two or more positive decimal numbers (with or without k or b)
+                separated by x, specifying the product of the indicated
                   values.
 
-
        All of the operands will be processed before any input is read.
 
 SIGNALS
        When dd receives either SIGINFO or SIGUSR1, dd will emit the current
        input and output block counts, total bytes written, total time elapsed,

@@ -333,123 +287,84 @@
        and the number of bytes per second to standard error. This is the same
        information format that dd emits when it successfully completes. Users
        may send SIGINFO via their terminal. The default character is ^T, see
        stty(1) for more information.
 
-
        For SIGINT, dd writes status information to standard error before
        exiting. dd takes the standard action for all other signals.
 
-
 USAGE
        See largefile(5) for the description of the behavior of dd when
-       encountering files greater than or equal to 2 Gbyte ( 2^31 bytes).
+     encountering files greater than or equal to 2 Gbyte (2^31 bytes).
 
+EXIT STATUS
+     The following exit values are returned:
+
+     0       The input file was copied successfully.
+
+     >0      An error occurred.
+
+     If an input error is detected and the noerror conversion has not been
+     specified, any partial output block will be written to the output file, a
+     diagnostic message will be written, and the copy operation will be
+     discontinued.  If some other error is detected, a diagnostic message will
+     be written and the copy operation will be discontinued.
+
 EXAMPLES
        Example 1 Copying from one tape drive to another
 
-
        The following example copies from tape drive 0 to tape drive 1, using a
        common historical device naming convention.
 
+           % dd if=/dev/rmt/0h of=/dev/rmt/1h
 
-         example% dd if=/dev/rmt/0h  of=/dev/rmt/1h
-
-
-
        Example 2 Stripping the first 10 bytes from standard input
 
-
        The following example strips the first 10 bytes from standard input:
 
+           % dd ibs=10 skip=1
 
-         example% dd ibs=10  skip=1
-
-
-
        Example 3 Reading a tape into an ASCII file
 
+     This example reads an EBCDIC tape blocked ten 80-byte EBCDIC card images
+     per block into the ASCII file x:
 
-       This example reads an EBCDIC tape blocked ten 80-byte EBCDIC card
-       images per block into the ASCII file x:
+           % dd if=/dev/tape of=x ibs=800 cbs=80 conv=ascii,lcase
 
-
-         example% dd if=/dev/tape of=x ibs=800 cbs=80 conv=ascii,lcase
-
-
-
        Example 4 Using conv=sync to write to tape
 
-
        The following example uses conv=sync when writing to a tape:
 
+           % tar cvf -. | compress | dd obs=1024k of=/dev/rmt/0 conv=sync
 
-         example% tar cvf - . | compress | dd obs=1024k of=/dev/rmt/0 conv=sync
+DIAGNOSTICS
+     f+p records in(out) numbers of full and partial blocks read(written)
 
-
-
 ENVIRONMENT VARIABLES
        See environ(5) for descriptions of the following environment variables
-       that affect the execution of dd: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES,
-       and NLSPATH.
+     that affect the execution of dd: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES, and
+     NLSPATH.
 
-EXIT STATUS
-       The following exit values are returned:
+INTERFACE STABILITY
+     Standard
 
-       0
-             The input file was copied successfully.
-
-
-       >0
-             An error occurred.
-
-
-
-       If an input error is detected and the noerror conversion has not been
-       specified, any partial output block will be written to the output file,
-       a diagnostic message will be written, and the copy operation will be
-       discontinued. If some other error is detected, a diagnostic message
-       will be written and the copy operation will be discontinued.
-
-ATTRIBUTES
-       See attributes(5) for descriptions of the following attributes:
-
-
-
-
-       +--------------------+-----------------+
-       |  ATTRIBUTE TYPE    | ATTRIBUTE VALUE |
-       +--------------------+-----------------+
-       |Interface Stability | Standard        |
-       +--------------------+-----------------+
-
 SEE ALSO
        cp(1), sed(1), tr(1), fcntl.h(3HEAD), attributes(5), environ(5),
        largefile(5), standards(5)
 
-DIAGNOSTICS
-       f+p records in(out)
-                              numbers of full and partial blocks read(written)
-
-
 NOTES
        Do not use dd to copy files between file systems having different block
        sizes.
 
-
        Using a  blocked device to copy a file will result in extra nulls being
        added to the file to pad the final block to the block boundary.
 
+     When dd reads from a pipe, using the ibs=X and obs=Y operands, the output
+     will always be blocked in chunks of size Y.  When bs=Z is used, the
+     output blocks will be whatever was available to be read from the pipe at
+     the time.
 
-       When  dd reads from a pipe, using the  ibs=X and  obs=Y operands, the
-       output will always be blocked in chunks of size Y. When bs=Z is used,
-       the output blocks will be whatever was available to be read from the
-       pipe at the time.
-
-
        When using dd to copy files to a tape device, the file size must be a
        multiple of the device sector size (for example, 512 Kbyte).  To  copy
        files of arbitrary size to a tape device, use  tar(1) or  cpio(1).
 
-
-
-                               December 12, 2014                        DD(1M)
+illumos                           May 4, 2019                          illumos