diff options
| -rw-r--r-- | usr/src/cmd/dd/dd.c | 50 | ||||
| -rw-r--r-- | usr/src/man/man1m/dd.1m | 1316 |
2 files changed, 722 insertions, 644 deletions
diff --git a/usr/src/cmd/dd/dd.c b/usr/src/cmd/dd/dd.c index 2cd372f604..3431548a91 100644 --- a/usr/src/cmd/dd/dd.c +++ b/usr/src/cmd/dd/dd.c @@ -98,6 +98,7 @@ #define SWAB 04 /* flag - swap bytes before conversion */ #define NERR 010 /* flag - proceed on input errors */ #define SYNC 020 /* flag - pad short input blocks with nulls */ +#define FULLBLOCK 040 /* flag - accumulate full blocks of input */ #define BADLIMIT 5 /* give up if no progress after BADLIMIT trys */ #define SVR4XLATE 0 /* use default EBCDIC translation */ #define BSDXLATE 1 /* use BSD-compatible EBCDIC translation */ @@ -106,10 +107,10 @@ "usage: dd [if=file] [of=file] [ibs=n|nk|nb|nxm] [obs=n|nk|nb|nxm]\n"\ " [bs=n|nk|nb|nxm] [cbs=n|nk|nb|nxm] [files=n] [skip=n]\n"\ " [iseek=n] [oseek=n] [seek=n] [stride=n] [istride=n]\n"\ - " [ostride=n] [count=n] [conv=[ascii] [,ebcdic][,ibm]\n"\ + " [ostride=n] [count=n] [conv=[ascii][,ebcdic][,ibm]\n"\ " [,asciib][,ebcdicb][,ibmb][,block|unblock][,lcase|ucase]\n"\ " [,swab][,noerror][,notrunc][,sync]]\n"\ - " [oflag=[dsync][sync]]\n" + " [iflag=[fullblock]] [oflag=[dsync][sync]]\n" /* Global references */ @@ -134,6 +135,7 @@ static unsigned cbc; /* number of bytes in the conversion buffer */ static int ibf; /* input file descriptor */ static int obf; /* output file descriptor */ static int cflag; /* conversion option flags */ +static int iflag; /* input flag options */ static int oflag; /* output flag options */ static int skipf; /* if skipf == 1, skip rest of input line */ static unsigned long long nifr; /* count of full input records */ @@ -486,6 +488,30 @@ siginfo_handler(int sig, siginfo_t *sip, void *ucp) nstats = 1; } +static ssize_t +iread(int fd, char *buf, size_t nbyte) +{ + ssize_t count; + + count = 0; + while (nbyte != 0) { + ssize_t nr = read(fd, buf, nbyte); + + if (nr < 0) + return (nr); + + if (nr == 0) + break; + buf += nr; + count += nr; + nbyte -= nr; + + if ((iflag & FULLBLOCK) == 0) + break; + } + return (count); +} + int main(int argc, char **argv) { @@ -664,6 +690,22 @@ main(int argc, char **argv) } continue; } + if (match("iflag=")) { + for (;;) { + if (match(",")) { + continue; + } + if (*string == '\0') { + break; + } + if (match("fullblock")) { + iflag |= FULLBLOCK; + continue; + } + goto badarg; + } + continue; + } if (match("oflag=")) { for (;;) { if (match(",")) { @@ -919,7 +961,7 @@ main(int argc, char **argv) /* Skip input blocks */ while (skip) { - ibc = read(ibf, (char *)ibuf, ibs); + ibc = iread(ibf, (char *)ibuf, ibs); if (ibc == (unsigned)-1) { if (++nbad > BADLIMIT) { (void) fprintf(stderr, "dd: %s\n", @@ -994,7 +1036,7 @@ main(int argc, char **argv) /* Read the next input block */ - ibc = read(ibf, (char *)ibuf, ibs); + ibc = iread(ibf, (char *)ibuf, ibs); if (istriden > 0 && lseek(ibf, istriden * ((off_t)ibs), SEEK_CUR) == -1) { diff --git a/usr/src/man/man1m/dd.1m b/usr/src/man/man1m/dd.1m index b2055ba264..237f816c52 100644 --- a/usr/src/man/man1m/dd.1m +++ b/usr/src/man/man1m/dd.1m @@ -46,663 +46,699 @@ .\" Copyright (c) 2014, Joyent, Inc. All rights Reserved. .\" Copyright (c) 2014 by Delphix. All rights reserved. .\" -.TH DD 1M "Dec 12, 2014" -.SH NAME -dd \- convert and copy a file -.SH SYNOPSIS -.LP -.nf -\fB/usr/bin/dd\fR [\fIoperand=value\fR]... -.fi - -.SH DESCRIPTION -.LP -The \fBdd\fR utility copies the specified input file to the specified output -with possible conversions. The standard input and output are used by default. +.Dd May 4, 2019 +.Dt DD 1M +.Os +.Sh NAME +.Nm dd +.Nd convert and copy a file +.Sh SYNOPSIS +.Nm +.Op Ar operand Ns = Ns Ar value +.Ar ... +.Sh DESCRIPTION +The +.Nm +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 \fBk\fR, -\fBb\fR, or \fBw\fR to specify multiplication by 1024, 512, or 2, respectively. -Numbers may also be separated by \fBx\fR to indicate multiplication. -.sp -.LP -The \fBdd\fR utility reads the input one block at a time, using the specified -input block size. \fBdd\fR then processes the block of data actually returned, -which could be smaller than the requested block size. \fBdd\fR applies any -conversions that have been specified and writes the resulting data to the -output in blocks of the specified output block size. -.sp -.LP -\fBcbs\fR is used only if \fBascii\fR, \fBasciib\fR, \fBunblock\fR, -\fBebcdic\fR, \fBebcdicb\fR, \fBibm\fR, \fBibmb\fR, or \fBblock\fR conversion -is specified. In the first two cases, \fBcbs\fR characters are copied into the -conversion buffer, any specified character mapping is done, trailing blanks are -trimmed, and a \fBNEWLINE\fR is added before sending the line to output. In the -last three cases, characters up to \fBNEWLINE\fR are read into the conversion -buffer and blanks are added to make up an output record of size \fBcbs\fR. -\fBASCII\fR files are presumed to contain \fBNEWLINE\fR characters. If -\fBcbs\fR is unspecified or \fB0\fR, the \fBascii\fR, \fBasciib\fR, -\fBebcdic\fR, \fBebcdicb\fR, \fBibm\fR, and \fBibmb\fR options convert the -character set without changing the input file's block structure. The -\fBunblock\fR and \fBblock\fR options become a simple file copy. -.sp -.LP -After completion, \fBdd\fR reports the number of whole and partial input and -output blocks. -.SH OPERANDS -.LP +physical I/O. +Sizes are specified in bytes; a number may end with +.Sy k , +.Sy b , +or +.Sy w +to specify multiplication by 1024, 512, or 2, respectively. +Numbers may also be separated by +.Sy x +to indicate multiplication. +.Pp +The +.Nm +utility reads the input one block at a time, using the specified +input block size. +.Nm +then processes the block of data actually returned, +which could be smaller than the requested block size unless the input flag +.Ar fullblock +is used. +.Nm +applies any conversions that have been specified and writes the resulting data +to the output in blocks of the specified output block size. +.Pp +.Cm cbs +is used only if +.Cm ascii , +.Cm asciib , +.Cm unblock , +.Cm ebcdic , +.Cm ebcdicb , +.Cm ibm , +.Cm ibmb , +or +.Cm block +conversion is specified. +In the first two cases, +.Cm cbs +characters are copied into the conversion buffer, any specified character +mapping is done, trailing blanks are trimmed, and a +.Cm NEWLINE +is added before sending the line to output. +In the last three cases, characters up to +.Cm NEWLINE +are read into the conversion buffer and blanks are added to make up an output +record of size +.Cm cbs . +.Cm ASCII +files are presumed to contain +.Cm NEWLINE +characters. +If +.Cm cbs +is unspecified or +.Cm 0 , +the +.Cm ascii , +.Cm asciib , +.Cm ebcdic , +.Cm ebcdicb , +.Cm ibm , +and +.Cm ibmb +options convert the character set without changing the input file's block +structure. +The +.Cm unblock +and +.Cm block +options become a simple file copy. +.Pp +After completion, +.Nm +reports the number of whole and partial input and output blocks. +.Sh OPERANDS The following operands are supported: -.sp -.ne 2 -.na -\fB\fBif=\fR\fIfile\fR\fR -.ad -.sp .6 -.RS 4n -Specifies the input path. Standard input is the default. -.RE - -.sp -.ne 2 -.na -\fB\fBof=\fR\fIfile\fR\fR -.ad -.sp .6 -.RS 4n -Specifies the output path. Standard output is the default. If the -\fBseek=\fR\fBexpr\fR conversion is not also specified, the output file will be -truncated before the copy begins, unless \fBconv=notrunc\fR is specified. If -\fBseek=\fR\fBexpr\fR is specified, but \fBconv=notrunc\fR is not, the effect -of the copy will be to preserve the blocks in the output file over which -\fBdd\fR 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.) -.RE - -.sp -.ne 2 -.na -\fB\fBibs=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Specifies the input block size in \fIn\fR bytes (default is \fB512\fR). -.RE - -.sp -.ne 2 -.na -\fB\fBobs=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Specifies the output block size in \fIn\fR bytes (default is \fB512\fR). -.RE - -.sp -.ne 2 -.na -\fB\fBbs=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Sets both input and output block sizes to \fIn\fR bytes, superseding \fBibs=\fR -and \fBobs=\fR. If no conversion other than \fBsync\fR,\fB noerror\fR, and -\fBnotrunc\fR is specified, each input block is copied to the output as a +.Bl -tag -width "if=file" +.It Cm if= Ns Ar file +.Pp +Specifies the input path. +Standard input is the default. +.It Cm of= Ns Ar file +.Pp +Specifies the output path. +Standard output is the default. +If the +.Cm seek Ns = Ns Ar expr +conversion is not also specified, the output file will be truncated before +the copy begins, unless +.Cm conv Ns = Ns Ar notrunc +is specified. +If +.Cm seek Ns = Ns Ar expr +is specified, but +.Cm conv Ns = Ns Ar notrunc +is not, the effect of the copy will be to preserve the blocks in the output +file over which +.Nm +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.) +.It Cm ibs Ns = Ns Ar n +.Pp +Specifies the input block size in +.Ar n +bytes (default is 512). +.It Cm obs Ns = Ns Ar n +.Pp +Specifies the output block size in +.Ar n +bytes (default is 512). +.It Cm bs Ns = Ns Ar n +.Pp +Sets both input and output block sizes to +.Ar n +bytes, superseding +.Cm ibs Ns = +and +.Cm obs Ns = . +If no conversion other than +.Cm sync , +.Cm noerror , +and +.Cm notrunc +is specified, each input block is copied to the output as a single block without aggregating short blocks. -.RE - -.sp -.ne 2 -.na -\fB\fBcbs=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Specifies the conversion block size for \fBblock\fR and \fBunblock\fR in bytes -by \fIn\fR (default is \fB0\fR). If \fBcbs=\fR is omitted or given a value of -\fB0\fR, using \fBblock\fR or \fBunblock\fR produces unspecified results. -.sp -This option is used only if \fBASCII\fR or \fBEBCDIC\fR conversion is -specified. For the \fBascii\fR and \fBasciib\fR operands, the input is handled -as described for the \fBunblock\fR operand except that characters are converted -to \fBASCII\fR before the trailing \fBSPACE\fR characters are deleted. For the -\fBebcdic\fR, \fBebcdicb\fR, \fBibm\fR, and \fBibmb\fR operands, the input is -handled as described for the \fBblock\fR operand except that the characters are -converted to \fBEBCDIC\fR or IBM \fBEBCDIC\fR after the trailing \fBSPACE\fR +.It Cm cbs Ns = Ns Ar n +.Pp +Specifies the conversion block size for +.Cm block +and +.Cm unblock +in bytes by +.Ar n +(default is +.Cm 0 Ns ). +If +.Cm cbs Ns = +is omitted or given a value of +.Cm 0 , +using +.Cm block +or +.Cm unblock +produces unspecified results. +.Pp +This option is used only if +.Cm ASCII +or +.Cm EBCDIC +conversion is specified. +For the +.Cm ascii +and +.Cm asciib +operands, the input is handled as described for the +.Cm unblock +operand except that characters are converted to +.Cm ASCII +before the trailing +.Cm SPACE +characters are deleted. +For the +.Cm ebcdic , +.Cm ebcdicb , +.Cm ibm , +and +.Cm ibmb +operands, the input is handled as described for the +.Cm block +operand except that the characters are converted to +.Cm EBCDIC +or IBM +.Cm EBCDIC +after the trailing +.Cm SPACE characters are added. -.RE - -.sp -.ne 2 -.na -\fB\fBfiles=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Copies and concatenates \fIn\fR input files before terminating (makes sense +.It Cm files Ns = Ns Ar n +.Pp +Copies and concatenates +.Ar n +input files before terminating (makes sense only where input is a magnetic tape or similar device). -.RE - -.sp -.ne 2 -.na -\fB\fBskip=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Skips \fIn\fR 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. -.RE - -.sp -.ne 2 -.na -\fB\fBiseek=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Seeks \fIn\fR blocks from beginning of input file before copying (appropriate -for disk files, where \fBskip\fR can be incredibly slow). -.RE - -.sp -.ne 2 -.na -\fB\fBoseek=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Seeks \fIn\fR blocks from beginning of output file before copying. -.RE - -.sp -.ne 2 -.na -\fB\fBseek=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Skips \fIn\fR 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 +.It Cm skip Ns = Ns Ar n +.Pp +Skips +.Ar 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. +.It Cm iseek Ns = Ns Ar n +.Pp +Seeks +.Ar n +blocks from beginning of input file before copying (appropriate +for disk files, where +.Cm skip +can be incredibly slow). +.It Cm oseek Ns = Ns Ar n +.Pp +Seeks +.Ar n +blocks from beginning of output file before copying. +.It Cm seek Ns = Ns Ar n +.Pp +Skips +.Ar 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. -.RE - -.sp -.ne 2 -.na -\fB\fBostride=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Writes every \fIn\fRth block (using the specified output block size) when -writing output. Skips \fIn\fR - 1 blocks after writing each record. -.RE - -.sp -.ne 2 -.na -\fB\fBistride=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Reads every \fIn\fRth block (using the specified input block size) when -reading input. Skips \fIn\fR - 1 blocks after reading each record. -.RE - -.sp -.ne 2 -.na -\fB\fBstride=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Reads every \fIn\fRth block (using the specified input block size) when -reading input. Skips \fIn\fR - 1 blocks after reading each record. Also -writes every \fIn\fRth block (using the specified output block size) when -writing output. Skips \fIn\fR - 1 blocks after writing each record. -.RE - -.sp -.ne 2 -.na -\fB\fBcount=\fR\fIn\fR\fR -.ad -.sp .6 -.RS 4n -Copies only \fIn\fR input blocks. -.RE - -.sp -.ne 2 -.na -\fB\fBconv=\fR\fIvalue\fR[\fB,\fR\fIvalue\fR.\|.\|.\|]\fR -.ad -.sp .6 -.RS 4n -Where \fIvalue\fRs are comma-separated symbols from the following list: -.sp -.ne 2 -.na -\fB\fBascii\fR\fR -.ad -.RS 11n -Converts \fBEBCDIC\fR to \fBASCII\fR. -.RE - -.sp -.ne 2 -.na -\fB\fBasciib\fR\fR -.ad -.RS 11n -Converts \fBEBCDIC\fR to \fBASCII\fR using \fBBSD\fR-compatible character -translations. -.RE - -.sp -.ne 2 -.na -\fB\fBebcdic\fR\fR -.ad -.RS 11n -Converts \fBASCII\fR to \fBEBCDIC\fR. If converting fixed-length \fBASCII\fR -records without NEWLINEs, sets up a pipeline with \fBdd conv=unblock\fR +.It Cm ostride Ns = Ns Ar n +.Pp +Writes every +.Ar n Ns +th block (using the specified output block size) when writing output. +Skips +.Ar n +- 1 blocks after writing each record. +.It Cm istride Ns = Ns Ar n +.Pp +Reads every +.Ar n Ns +th block (using the specified input block size) when reading input. +Skips +.Ar n +- 1 blocks after reading each record. +.It Cm stride Ns = Ns Ar n +.Pp +Reads every +.Ar n Ns +th block (using the specified input block size) when reading input. +Skips +.Ar n +- 1 blocks after reading each record. +Also writes every +.Ar n Ns +th block (using the specified output block size) when writing output. +Skips +.Ar n +- 1 blocks after writing each record. +.It Cm count Ns = Ns Ar n +.Pp +Copies only +.Ar n +input blocks. +.It Cm conv Ns = Ns Ar value Ns Op , Ns Ar value Ns ... +.Pp +Where +.Ar value Ns +s are comma-separated symbols from the following list: +.Bl -hang +.It Cm ascii +Converts +.Cm EBCDIC +to +.Cm ASCII . +.sp +.It Cm asciib +Converts +.Cm EBCDIC +to +.Cm ASCII +using +.Cm BSD Ns +-compatible character translations. +.It Cm ebcdic +Converts +.Cm ASCII +to +.Cm EBCDIC . +If converting fixed-length +.Cm ASCII +records without +.Cm NEWLINE Ns +s, sets up a pipeline with +.Nm +.Cm conv Ns = Ns Ar unblock beforehand. -.RE - -.sp -.ne 2 -.na -\fB\fBebcdicb\fR\fR -.ad -.RS 11n -Converts \fBASCII\fR to \fBEBCDIC\fR using \fBBSD\fR-compatible character -translations. If converting fixed-length \fBASCII\fR records without -\fBNEWLINE\fRs, sets up a pipeline with \fBdd conv=unblock\fR beforehand. -.RE - -.sp -.ne 2 -.na -\fB\fBibm\fR\fR -.ad -.RS 11n -Slightly different map of \fBASCII\fR to \fBEBCDIC\fR. If converting -fixed-length \fBASCII\fR records without \fBNEWLINE\fRs, sets up a pipeline -with \fBdd conv=unblock\fR beforehand. -.RE - -.sp -.ne 2 -.na -\fB\fBibmb\fR\fR -.ad -.RS 11n -Slightly different map of \fBASCII\fR to \fBEBCDIC\fR using -\fBBSD\fR-compatible character translations. If converting fixed-length -\fBASCII\fR records without \fBNEWLINE\fRs, sets up a pipeline with \fBdd -conv=unblock\fR beforehand. -.RE - -The \fBascii\fR (or \fBasciib\fR), \fBebcdic\fR (or \fBebcdicb\fR), and -\fBibm\fR (or \fBibmb\fR) values are mutually exclusive. -.sp -.ne 2 -.na -\fB\fBblock\fR\fR -.ad -.RS 11n -Treats the input as a sequence of \fBNEWLINE\fR-terminated or -\fBEOF\fR-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 \fBNEWLINE\fR character is removed from the -input line. \fBSPACE\fR 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. -.RE - -.sp -.ne 2 -.na -\fB\fBunblock\fR\fR -.ad -.RS 11n -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 \fBSPACE\fR -characters, and append a \fBNEWLINE\fR character. -.RE - -The \fBblock\fR and \fBunblock\fR values are mutually exclusive. -.sp -.ne 2 -.na -\fB\fBlcase\fR\fR -.ad -.RS 9n -Maps upper-case characters specified by the \fBLC_CTYPE\fR keyword -\fBtolower\fR to the corresponding lower-case character. Characters for which -no mapping is specified are not modified by this conversion. -.RE - -.sp -.ne 2 -.na -\fB\fBucase\fR\fR -.ad -.RS 9n -Maps lower-case characters specified by the \fBLC_CTYPE\fR keyword -\fBtoupper\fR to the corresponding upper-case character. Characters for which -no mapping is specified are not modified by this conversion. -.RE - -The \fBlcase\fR and \fBucase\fR symbols are mutually exclusive. -.sp -.ne 2 -.na -\fB\fBswab\fR\fR -.ad -.RS 11n -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. -.RE - -.sp -.ne 2 -.na -\fB\fBnoerror\fR\fR -.ad -.RS 11n -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 -\fBsync\fR conversion is specified, the missing input is replaced with null -bytes and processed normally. Otherwise, the input block will be omitted from -the output. -.RE - -.sp -.ne 2 -.na -\fB\fBnotrunc\fR\fR -.ad -.RS 11n -Does not truncate the output file. Preserves blocks in the output file not -explicitly written by this invocation of \fBdd\fR. (See also the preceding -\fBof=\fR\fIfile\fR operand.) -.RE - -.sp -.ne 2 -.na -\fB\fBsync\fR\fR -.ad -.RS 11n -Pads every input block to the size of the \fBibs=\fR buffer, appending null -bytes. (If either \fBblock\fR or \fBunblock\fR is also specified, appends -\fBSPACE\fR characters, rather than null bytes.) -.RE - -.RE - -.sp -.ne 2 -.na -\fB\fBoflag=\fR\fIvalue\fR[\fB,\fR\fIvalue\fR.\|.\|.\|]\fR +.It Cm ebcdicb +Converts +.Cm ASCII +to +.Cm EBCDIC +using +.Cm BSD Ns +-compatible character translations. +If converting fixed-length +.Cm ASCII +records without +.Cm NEWLINE Ns +s, sets up a pipeline with +.Nm +.Cm conv Ns = Ns Ar unblock +beforehand. +.It Cm ibm +Slightly different map of +.Cm ASCII +to +.Cm EBCDIC . +If converting fixed-length +.Cm ASCII +records without +.Cm NEWLINE Ns +s, sets up a pipeline with +.Nm +.Cm conv Ns = Ns Ar unblock +beforehand. +.It Cm ibmb +Slightly different map of +.Cm ASCII +to +.Cm EBCDIC +using +.Cm BSD Ns +-compatible character translations. +If converting fixed-length +.Cm ASCII +records without +.Cm NEWLINE Ns +s, sets up a pipeline with +.Nm +.Cm conv Ns = Ns Ar unblock +beforehand. +.El +.Pp +The +.Cm ascii +(or +.Cm asciib Ns ), +.Cm ebcdic +(or +.Cm ebcdicb Ns ), +and +.Cm ibm +(or +.Cm ibmb ) +values are mutually exclusive. +.Bl -hang +.It Cm block +Treats the input as a sequence of +.Cm NEWLINE Ns +-terminated or +.Cm EOF Ns +-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 +.Cm NEWLINE +character is removed from the input line. +.Cm 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. +.It Cm 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 +.Cm SPACE +characters, and append a +.Cm NEWLINE +character. +.El +.Pp +The +.Cm block +and +.Cm unblock +values are mutually exclusive. +.Bl -hang +.It Cm lcase +Maps upper-case characters specified by the +.Cm LC_CTYPE +keyword +.Cm tolower +to the corresponding lower-case character. +Characters for which no mapping is specified are not modified by this +conversion. +.It Cm ucase +Maps lower-case characters specified by the +.Cm LC_CTYPE +keyword +.Cm toupper +to the corresponding upper-case character. +Characters for which no mapping is specified are not modified by this +conversion. +.El +.Pp +The +.Cm lcase +and +.Cm ucase +symbols are mutually exclusive. +.Bl -hang +.It Cm 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. +.It Cm 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 +.Cm 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. +.It Cm notrunc +Does not truncate the output file. +Preserves blocks in the output file not explicitly written by this invocation +of +.Nm . +(See also the preceding +.Cm of Ns = Ns Ar file +operand.) +.It Cm sync +Pads every input block to the size of the +.Cm ibs Ns = +buffer, appending null bytes. +(If either +.Cm block +or +.Cm unblock +is also specified, appends +.Cm SPACE +characters, rather than null bytes.) +.El +.It Cm iflag Ns = Ns Ar value Ns Op , Ns Ar value ... +.Pp +Where +.Ar value Ns +s are comma-separated symbols from the following list which +affect the behavior of reading from the input file: +.Bl -hang +.It Cm fullblock +Accumulate full blocks of input. +.El +.It Cm oflag Ns = Ns Ar value Ns Op , Ns Ar value ... .ad .sp .6 -Where \fIvalue\fRs are comma-separated symbols from the following list which +Where +.Ar value Ns +s are comma-separated symbols from the following list which affect the behavior of writing the output file: -.sp -.ne 2 -.na -\fB\fBdsync\fR\fR -.ad -.RS 11n -The output file is opened with the \fBO_DSYNC\fR flag set. All data writes will -be synchronous. For more information on \fBO_DSYNC\fR see \fBfcntl.h\fR(3HEAD). -.RE - -.sp -.ne 2 -.na -\fB\fBsync\fR\fR -.ad -.RS 11n -The output file is opened with the \fBO_SYNC\fR flag set. All data and metadata -writes will be synchronous. For more information on \fBO_SYNC\fR see -\fBfcntl.h\fR(3HEAD). -.RE - -.sp -.LP -If operands other than \fBconv=\fR and \fBoflag=\fR are specified more than once, -the last specified \fBoperand=\fR\fIvalue\fR is used. -.sp -.LP -For the \fBbs=\fR, \fBcbs=\fR, \fBibs=\fR, and \fBobs=\fR operands, the -application must supply an expression specifying a size in bytes. The -expression, \fBexpr\fR, can be: -.RS +4 -.TP -1. +.Bl -hang +.It Cm dsync +The output file is opened with the +.Cm O_DSYNC +flag set. +All data writes will be synchronous. +For more information on +.Cm O_DSYNC +see +.Xr fcntl.h 3HEAD . +.It Cm sync +The output file is opened with the +.Cm O_SYNC . +All data and metadata writes will be synchronous. +For more information on +.Cm O_SYNC +see +.Xr fcntl.h 3HEAD . +.El +.El +.Pp +If operands other than +.Cm conv Ns = +and +.Cm oflag Ns = +are specified more than once, the last specified +.Cm operand Ns = Ns Ar value +is used. +.Pp +For the +.Cm bs Ns = , +.Cm cbs Ns = , +.Cm ibs Ns = , +and +.Cm obs Ns = +operands, the application must supply an expression specifying a size in bytes. +The expression, +.Cm expr , +can be: +.Bl -enum -offset indent -compact +.It a positive decimal number -.RE -.RS +4 -.TP -2. -a positive decimal number followed by \fBk\fR, specifying multiplication by -1024 -.RE -.RS +4 -.TP -3. -a positive decimal number followed by \fBM\fR, specifying multiplication by -1024*1024 -.RE -.RS +4 -.TP -4. -a positive decimal number followed by \fBG\fR, specifying multiplication by -1024*1024*1024 -.RE -.RS +4 -.TP -5. -a positive decimal number followed by \fBT\fR, specifying multiplication by -1024*1024*1024*1024 -.RE -.RS +4 -.TP -6. -a positive decimal number followed by \fBP\fR, specifying multiplication by -1024*1024*1024*1024*1024 -.RE -.RS +4 -.TP -7. -a positive decimal number followed by \fBE\fR, specifying multiplication by -1024*1024*1024*1024*1024*1024 -.RE -.RS +4 -.TP -8. -a positive decimal number followed by \fBZ\fR, specifying multiplication by -1024*1024*1024*1024*1024*1024*1024 -.RE -.RS +4 -.TP -9. -a positive decimal number followed by \fBb\fR, specifying multiplication by -512 -.RE -.RS +4 -.TP -10. -two or more positive decimal numbers (with or without \fBk\fR or \fBb\fR) -separated by \fBx\fR, specifying the product of the indicated values. -.RE -.sp -.LP +.Pp +.It +a positive decimal number followed by +.Sy k , +specifying multiplication by 1024 +.Pp +.It +a positive decimal number followed by +.Sy M , +specifying multiplication by 1024*1024 +.Pp +.It +a positive decimal number followed by +.Sy G , +specifying multiplication by 1024*1024*1024 +.Pp +.It +a positive decimal number followed by +.Sy T , +specifying multiplication by 1024*1024*1024*1024 +.Pp +.It +a positive decimal number followed by +.Sy P , +specifying multiplication by 1024*1024*1024*1024*1024 +.Pp +.It +a positive decimal number followed by +.Sy E , +specifying multiplication by 1024*1024*1024*1024*1024*1024 +.Pp +.It +a positive decimal number followed by +.Sy Z , +specifying multiplication by 1024*1024*1024*1024*1024*1024*1024 +.Pp +.It +a positive decimal number followed by +.Sy b , +specifying multiplication by 512 +.Pp +.It +two or more positive decimal numbers (with or without +.Sy k +or +.Sy b ) +separated by +.Sy x , +specifying the product of the indicated values. +.El +.Pp All of the operands will be processed before any input is read. -.SH SIGNALS -.LP -When \fBdd\fR receives either SIGINFO or SIGUSR1, \fBdd\fR will emit the current -input and output block counts, total bytes written, total time elapsed, and the -number of bytes per second to standard error. This is the same information -format that \fBdd\fR emits when it successfully completes. Users may send -SIGINFO via their terminal. The default character is ^T, see \fBstty\fR(1) for -more information. -.sp -.LP -For \fBSIGINT\fR, \fBdd\fR writes status information to standard error before -exiting. \fBdd\fR takes the standard action for all other signals. - -.SH USAGE -.LP -See \fBlargefile\fR(5) for the description of the behavior of \fBdd\fR when -encountering files greater than or equal to 2 Gbyte ( 2^31 bytes). -.SH EXAMPLES -.LP -\fBExample 1 \fRCopying from one tape drive to another -.sp -.LP -The following example copies from tape drive \fB0\fR to tape drive \fB1\fR, -using a common historical device naming convention. - -.sp -.in +2 -.nf -example% \fBdd if=/dev/rmt/0h of=/dev/rmt/1h\fR -.fi -.in -2 -.sp - -.LP -\fBExample 2 \fRStripping the first 10 bytes from standard input -.sp -.LP -The following example strips the first 10 bytes from standard input: - -.sp -.in +2 -.nf -example% \fBdd ibs=10 skip=1\fR -.fi -.in -2 -.sp - -.LP -\fBExample 3 \fRReading a tape into an ASCII file -.sp -.LP -This example reads an \fBEBCDIC\fR tape blocked ten 80-byte \fBEBCDIC\fR card -images per block into the \fBASCII\fR file \fBx\fR: - -.sp -.in +2 -.nf -example% \fBdd if=/dev/tape of=x ibs=800 cbs=80 conv=ascii,lcase\fR -.fi -.in -2 -.sp - -.LP -\fBExample 4 \fRUsing conv=sync to write to tape -.sp -.LP -The following example uses \fBconv=sync\fR when writing to a tape: - -.sp -.in +2 -.nf -example% \fBtar cvf - . | compress | dd obs=1024k of=/dev/rmt/0 conv=sync\fR -.fi -.in -2 -.sp - -.SH ENVIRONMENT VARIABLES -.LP -See \fBenviron\fR(5) for descriptions of the following environment variables -that affect the execution of \fBdd\fR: \fBLANG\fR, \fBLC_ALL\fR, -\fBLC_CTYPE\fR, \fBLC_MESSAGES\fR, and \fBNLSPATH\fR. -.SH EXIT STATUS -.LP +.Sh SIGNALS +When +.Nm +receives either SIGINFO or SIGUSR1, +.Nm +will emit the current input and output block counts, total bytes written, +total time elapsed, and the number of bytes per second to standard error. +This is the same information format that +.Nm +emits when it successfully completes. +Users may send SIGINFO via their terminal. +The default character is ^T, see +.Xr stty 1 +for more information. +.Pp +For +.Sy SIGINT , +.Nm +writes status information to standard error before exiting. +.Nm +takes the standard action for all other signals. +.Sh USAGE +See +.Xr largefile 5 +for the description of the behavior of +.Nm +when encountering files greater than or equal to 2 Gbyte (2^31 bytes). +.Sh EXIT STATUS The following exit values are returned: -.sp -.ne 2 -.na -\fB\fB0\fR\fR -.ad -.RS 6n +.Bl -tag -width ".It Cm >0" +.It Cm 0 The input file was copied successfully. -.RE - -.sp -.ne 2 -.na -\fB\fB>0\fR\fR -.ad -.RS 6n +.It Cm >0 An error occurred. -.RE - -.sp -.LP -If an input error is detected and the \fBnoerror\fR 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 +.El +.Pp +If an input error is detected and the +.Cm 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. -.SH ATTRIBUTES -.LP -See \fBattributes\fR(5) for descriptions of the following attributes: -.sp - -.sp -.TS -box; -c | c -l | l . -ATTRIBUTE TYPE ATTRIBUTE VALUE -_ -Interface Stability Standard -.TE - -.SH SEE ALSO -.LP -\fBcp\fR(1), \fBsed\fR(1), \fBtr\fR(1), \fBfcntl.h\fR(3HEAD), -\fBattributes\fR(5), \fBenviron\fR(5), \fBlargefile\fR(5), \fBstandards\fR(5) -.SH DIAGNOSTICS -.ne 2 -.na -\fB\fBf+p records in(out)\fR\fR -.ad -.RS 23n +.Sh EXAMPLES +.Bl -ohang +.It Sy Example 1 No Copying from one tape drive to another +.Pp +The following example copies from tape drive +.Sy 0 +to tape drive +.Sy 1 , +using a common historical device naming convention. +.Pp +.Dl % dd if=/dev/rmt/0h of=/dev/rmt/1h +.It Sy Example 2 No Stripping the first 10 bytes from standard input +.Pp +The following example strips the first 10 bytes from standard input: +.Pp +.Dl % dd ibs=10 skip=1 +.It Sy Example 3 No Reading a tape into an ASCII file +.Pp +This example reads an +.Cm EBCDIC +tape blocked ten 80-byte +.Cm EBCDIC +card images per block into the +.Cm ASCII +file +.Sy x : +.Pp +.Dl % dd if=/dev/tape of=x ibs=800 cbs=80 conv=ascii,lcase +.It Sy Example 4 No Using conv=sync to write to tape +.Pp +The following example uses +.Cm conv Ns = Ns Ar sync +when writing to a tape: +.Pp +.Dl % tar cvf - . | compress | dd obs=1024k of=/dev/rmt/0 conv=sync +.El +.Sh DIAGNOSTICS +.Bl -hang +.It Sy f+p records in(out) numbers of full and partial blocks read(written) -.RE - -.SH NOTES -.LP -Do not use \fBdd\fR to copy files between file systems having different block -sizes. -.sp -.LP +.El +.Sh ENVIRONMENT VARIABLES +See +.Xr environ 5 +for descriptions of the following environment variables +that affect the execution of +.Nm : +.Ev LANG , +.Ev LC_ALL , +.Ev LC_CTYPE , +.Ev LC_MESSAGES , +and +.Ev NLSPATH . +.Sh INTERFACE STABILITY +Standard +.Sh SEE ALSO +.Xr cp 1 , +.Xr sed 1 , +.Xr tr 1 , +.Xr fcntl.h 3HEAD , +.Xr attributes 5 , +.Xr environ 5 , +.Xr largefile 5 , +.Xr standards 5 +.Sh NOTES +Do not use +.Nm +to copy files between file systems having different block sizes. +.Pp 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. -.sp -.LP -When \fBdd\fR reads from a pipe, using the \fBibs=X\fR and \fBobs=Y\fR -operands, the output will always be blocked in chunks of size Y. When -\fBbs=Z\fR is used, the output blocks will be whatever was available to be read +.Pp +When +.Nm +reads from a pipe, using the +.Cm ibs Ns = Ns Ar X +and +.Cm obs Ns = Ns Ar Y +operands, the output will always be blocked in chunks of size Y. +When +.Cm bs Ns = Ns Ar Z +is used, the output blocks will be whatever was available to be read from the pipe at the time. -.sp -.LP -When using \fBdd\fR 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 \fBtar\fR(1) or \fBcpio\fR(1). +.Pp +When using +.Nm +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 +.Xr tar 1 +or +.Xr cpio 1 . |