dd Command: Conversion Symbols, Flags, and Options

information to print to stderr; ’none’ suppresses everything but error messages, ’noxfer’ suppresses the final transfer statistics, ’progress’ shows periodic transfer statistics N and BYTES may be followed by the following multiplicative suffixes: c=1, w=2, b=512, kB=1000, K=1024, MB=1000*1000, M=1024*1024, xM=M, GB=1000*1000*1000, G=1024*1024*1024, and so on for T, P, E, Z, Y. Binary pre‐ fixes can be used, too: KiB=K, MiB=M, and so on. If N ends in ’B’, it counts bytes not blocks. Each CONV symbol may be: ascii from EBCDIC to ASCII ebcdic from ASCII to EBCDIC ibm from ASCII to alternate EBCDIC block pad newline-terminated records with spaces to cbs-size unblock replace trailing spaces in cbs-size records with newline lcase change upper case to lower case ucase change lower case to upper case sparse try to seek rather than write all-NUL output blocks swab swap every pair of input bytes sync pad every input block with NULs to ibs-size; when used with block or unblock, pad with spaces rather than NULs excl fail if the output file already exists nocreat do not create the output file notrunc do not truncate the output file noerror continue after read errors fdatasync physically write output file data before finishing fsync likewise, but also write metadata Each FLAG symbol may be: append append mode (makes sense only for output; conv=notrunc suggested) direct use direct I/O for data directory fail unless a directory dsync use synchronized I/O for data sync likewise, but also for metadata fullblock accumulate full blocks of input (iflag only) nonblock use non-blocking I/O noatime do not update access time nocache Request to drop cache. See also oflag=sync noctty do not assign controlling terminal from file nofollow do not follow symlinks Sending a USR1 signal to a running ’dd’ process makes it print I/O statistics to standard error and then resume copying. Options are: --help display this help and exit --version output version information and exit AUTHOR Written by Paul Rubin, David MacKenzie, and Stuart Kemp. REPORTING BUGS GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT Copyright © 2022 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO Full documentation <https://www.gnu.org/software/coreutils/dd> or available locally via: info '(coreutils) dd invocation' GNU coreutils 9.1 January 2024 DD(1)

This section continues the documentation for the `dd` command, detailing various conversion symbols for the `conv` option (like case conversion, padding, and error handling) and flag symbols for the `iflag` and `oflag` options (such as append mode, direct I/O, and synchronization). It also mentions the effect of sending a USR1 signal to a running `dd` process, which causes it to print I/O statistics. Finally, it lists help and version options and provides information about the author, bug reporting, copyright, and further documentation.