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diff --git a/man/shred.1 b/man/shred.1 new file mode 100644 index 0000000..6a973a3 --- /dev/null +++ b/man/shred.1 @@ -0,0 +1,107 @@ +.\" DO NOT MODIFY THIS FILE! It was generated by help2man 1.47.3. +.TH SHRED "1" "July 2018" "GNU coreutils 8.30" "User Commands" +.SH NAME +shred \- overwrite a file to hide its contents, and optionally delete it +.SH SYNOPSIS +.B shred +[\fI\,OPTION\/\fR]... \fI\,FILE\/\fR... +.SH DESCRIPTION +.\" Add any additional description here +.PP +Overwrite the specified FILE(s) repeatedly, in order to make it harder +for even very expensive hardware probing to recover the data. +.PP +If FILE is \-, shred standard output. +.PP +Mandatory arguments to long options are mandatory for short options too. +.TP +\fB\-f\fR, \fB\-\-force\fR +change permissions to allow writing if necessary +.TP +\fB\-n\fR, \fB\-\-iterations\fR=\fI\,N\/\fR +overwrite N times instead of the default (3) +.TP +\fB\-\-random\-source\fR=\fI\,FILE\/\fR +get random bytes from FILE +.TP +\fB\-s\fR, \fB\-\-size\fR=\fI\,N\/\fR +shred this many bytes (suffixes like K, M, G accepted) +.TP +\fB\-u\fR +deallocate and remove file after overwriting +.TP +\fB\-\-remove\fR[=\fI\,HOW\/\fR] +like \fB\-u\fR but give control on HOW to delete; See below +.TP +\fB\-v\fR, \fB\-\-verbose\fR +show progress +.TP +\fB\-x\fR, \fB\-\-exact\fR +do not round file sizes up to the next full block; +.IP +this is the default for non\-regular files +.TP +\fB\-z\fR, \fB\-\-zero\fR +add a final overwrite with zeros to hide shredding +.TP +\fB\-\-help\fR +display this help and exit +.TP +\fB\-\-version\fR +output version information and exit +.PP +Delete FILE(s) if \fB\-\-remove\fR (\fB\-u\fR) is specified. The default is not to remove +the files because it is common to operate on device files like \fI\,/dev/hda\/\fP, +and those files usually should not be removed. +The optional HOW parameter indicates how to remove a directory entry: +\&'unlink' => use a standard unlink call. +\&'wipe' => also first obfuscate bytes in the name. +\&'wipesync' => also sync each obfuscated byte to disk. +The default mode is 'wipesync', but note it can be expensive. +.PP +CAUTION: Note that shred relies on a very important assumption: +that the file system overwrites data in place. This is the traditional +way to do things, but many modern file system designs do not satisfy this +assumption. The following are examples of file systems on which shred is +not effective, or is not guaranteed to be effective in all file system modes: +.PP +* log\-structured or journaled file systems, such as those supplied with +AIX and Solaris (and JFS, ReiserFS, XFS, Ext3, etc.) +.PP +* file systems that write redundant data and carry on even if some writes +fail, such as RAID\-based file systems +.PP +* file systems that make snapshots, such as Network Appliance's NFS server +.PP +* file systems that cache in temporary locations, such as NFS +version 3 clients +.PP +* compressed file systems +.PP +In the case of ext3 file systems, the above disclaimer applies +(and shred is thus of limited effectiveness) only in data=journal mode, +which journals file data in addition to just metadata. In both the +data=ordered (default) and data=writeback modes, shred works as usual. +Ext3 journaling modes can be changed by adding the data=something option +to the mount options for a particular file system in the \fI\,/etc/fstab\/\fP file, +as documented in the mount man page (man mount). +.PP +In addition, file system backups and remote mirrors may contain copies +of the file that cannot be removed, and that will allow a shredded file +to be recovered later. +.SH AUTHOR +Written by Colin Plumb. +.SH "REPORTING BUGS" +GNU coreutils online help: <https://www.gnu.org/software/coreutils/> +.br +Report shred translation bugs to <https://translationproject.org/team/> +.SH COPYRIGHT +Copyright \(co 2018 Free Software Foundation, Inc. +License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. +.br +This is free software: you are free to change and redistribute it. +There is NO WARRANTY, to the extent permitted by law. +.SH "SEE ALSO" +Full documentation at: <https://www.gnu.org/software/coreutils/shred> +.br +or available locally via: info \(aq(coreutils) shred invocation\(aq |