\fBzstd\fR command line is generally similar to gzip, but features the following differences :
- Source files are preserved by default
It's possible to remove them automatically by using \fB--rm\fR command
- - By default, when compressing a single file, \fBzstd\fR displays progress notifications and result summary.
+ - When compressing a single file, \fBzstd\fR displays progress notifications and result summary by default.
Use \fB-q\fR to turn them off
.SH OPTIONS
+
+.
+.SS "Integer suffixes and special values"
+In most places where an integer argument is expected,
+an optional suffix is supported to easily indicate large integers.
+There must be no space between the integer and the suffix.
+.TP
+.B KiB
+Multiply the integer by 1,024 (2^10).
+.BR Ki ,
+.BR K ,
+and
+.B KB
+are accepted as synonyms for
+.BR KiB .
+.TP
+.B MiB
+Multiply the integer by 1,048,576 (2^20).
+.BR Mi ,
+.BR M ,
+and
+.B MB
+are accepted as synonyms for
+.BR MiB .
+
+.
+.SS "Operation mode"
+If multiple operation mode options are given,
+the last one takes effect.
+.TP
+.BR \-z ", " \-\-compress
+Compress.
+This is the default operation mode when no operation mode option
+is specified and no other operation mode is implied from
+the command name (for example,
+.B unzstd
+implies
+.BR \-\-decompress ).
+.TP
+.BR \-d ", " \-\-decompress ", " \-\-uncompress
+Decompress.
+.TP
+.BR \-t ", " \-\-test
+Test the integrity of compressed
+.IR files .
+This option is equivalent to
+.B "\-\-decompress \-\-stdout"
+except that the decompressed data is discarded instead of being
+written to standard output.
+No files are created or removed.
+.TP
+.B \-b#
+ benchmark file(s) using compression level #
+.TP
+.B \--train FILEs
+ use FILEs as training set to create a dictionary. The training set should contain a lot of small files (> 100).
+
+.
+.SS "Operation modifiers"
.TP
.B \-#
- # compression level [1-22] (default:3)
+ # compression level [1-19] (default:3)
.TP
-.BR \-d ", " --decompress
- decompression
+.BR \--ultra
+ unlocks high compression levels 20+ (maximum 22), using a lot more memory
.TP
.B \-D file
use `file` as Dictionary to compress or decompress FILE(s)
.TP
+.BR \--no-dictID
+ do not store dictionary ID within frame header (dictionary compression).
+ the decoder will have to rely on implicit knowledge about which dictionary to use, it won't be able to check if it's correct.
+.TP
.B \-o file
save result into `file` (only possible with a single INPUT-FILE)
.TP
.BR \-c ", " --stdout
force write to standard output, even if it is the console
.TP
+.BR \--[no-]sparse
+ enable / disable sparse FS support, to make files with many zeroes smaller on disk.
+ default : enabled when output is into a file, and disabled when output is stdout.
+ This setting overrides default and can force sparse mode over stdout.
+.TP
.BR \--rm
remove source file(s) after successful compression or decompression
.TP
suppress warnings, interactivity and notifications.
specify twice to suppress errors too.
.TP
-.BR \-C ", " --check
- add integrity check computed from uncompressed data
+.BR \-C ", " --[no-]check
+ add integrity check computed from uncompressed data (default : enabled)
.TP
.BR \-t ", " --test
Test the integrity of compressed files. This option is equivalent to \fB--decompress --stdout > /dev/null\fR.
Typical gains range from ~10% (at 64KB) to x5 better (at <1KB).
.TP
.B \--train FILEs
- use FILEs as training set to create a dictionary.
- The training set should contain a lot of small files (> 100).
- and weight typically 100x the target dictionary size
- (for example, 10 MB for a 100 KB dictionary)
+ use FILEs as training set to create a dictionary. The training set should contain a lot of small files (> 100),
+and weight typically 100x the target dictionary size (for example, 10 MB for a 100 KB dictionary)
.TP
.B \-o file
dictionary saved into `file` (default: dictionary)
.B \-b#
benchmark file(s) using compression level #
.TP
+.B \-e#
+ benchmark file(s) using multiple compression levels, from -b# to -e# (included).
+.TP
.B \-i#
minimum evaluation time, in seconds (default : 3s), benchmark mode only
.TP
return result;
}
+typedef enum { zom_compress, zom_decompress, zom_test, zom_bench, zom_train } zstd_operation_mode;
#define CLEAN_RETURN(i) { operationResult = (i); goto _end; }
int main(int argCount, const char* argv[])
{
int argNb,
- bench=0,
- decode=0,
- testmode=0,
forceStdout=0,
main_pause=0,
nextEntryIsDictionary=0,
operationResult=0,
- dictBuild=0,
nextArgumentIsOutFileName=0,
nextArgumentIsMaxDict=0,
nextArgumentIsDictID=0,
nextArgumentIsFile=0,
ultra=0,
lastCommand = 0;
+ zstd_operation_mode operation = zom_compress;
int cLevel = ZSTDCLI_CLEVEL_DEFAULT;
int cLevelLast = 1;
unsigned recursive = 0;
/* init */
(void)recursive; (void)cLevelLast; /* not used when ZSTD_NOBENCH set */
(void)dictCLevel; (void)dictSelect; (void)dictID; /* not used when ZSTD_NODICT set */
- (void)decode; (void)cLevel; (void)testmode; /* not used when ZSTD_NOCOMPRESS set */
+ (void)cLevel; /* not used when ZSTD_NOCOMPRESS set */
(void)ultra; (void)memLimit; /* not used when ZSTD_NODECOMPRESS set */
if (filenameTable==NULL) { DISPLAY("zstd: %s \n", strerror(errno)); exit(1); }
filenameTable[0] = stdinmark;
}
/* preset behaviors */
- if (!strcmp(programName, ZSTD_UNZSTD)) decode=1;
- if (!strcmp(programName, ZSTD_CAT)) { decode=1; forceStdout=1; displayLevel=1; outFileName=stdoutmark; }
+ if (!strcmp(programName, ZSTD_UNZSTD)) operation=zom_decompress;
+ if (!strcmp(programName, ZSTD_CAT)) { operation=zom_decompress; forceStdout=1; displayLevel=1; outFileName=stdoutmark; }
/* command switches */
for (argNb=1; argNb<argCount; argNb++) {
/* long commands (--long-word) */
if (!strcmp(argument, "--")) { nextArgumentIsFile=1; continue; } /* only file names allowed from now on */
- if (!strcmp(argument, "--decompress")) { decode=1; continue; }
+ if (!strcmp(argument, "--compress")) { operation=zom_compress; continue; }
+ if (!strcmp(argument, "--decompress")) { operation=zom_decompress; continue; }
+ if (!strcmp(argument, "--uncompress")) { operation=zom_decompress; continue; }
if (!strcmp(argument, "--force")) { FIO_overwriteMode(); continue; }
if (!strcmp(argument, "--version")) { displayOut=stdout; DISPLAY(WELCOME_MESSAGE); CLEAN_RETURN(0); }
if (!strcmp(argument, "--help")) { displayOut=stdout; CLEAN_RETURN(usage_advanced(programName)); }
if (!strcmp(argument, "--no-dictID")) { FIO_setDictIDFlag(0); continue; }
if (!strcmp(argument, "--sparse")) { FIO_setSparseWrite(2); continue; }
if (!strcmp(argument, "--no-sparse")) { FIO_setSparseWrite(0); continue; }
- if (!strcmp(argument, "--test")) { testmode=1; decode=1; continue; }
- if (!strcmp(argument, "--train")) { dictBuild=1; outFileName=g_defaultDictName; continue; }
+ if (!strcmp(argument, "--test")) { operation=zom_test; continue; }
+ if (!strcmp(argument, "--train")) { operation=zom_train; outFileName=g_defaultDictName; continue; }
if (!strcmp(argument, "--maxdict")) { nextArgumentIsMaxDict=1; lastCommand=1; continue; }
if (!strcmp(argument, "--dictID")) { nextArgumentIsDictID=1; lastCommand=1; continue; }
if (!strcmp(argument, "--keep")) { FIO_setRemoveSrcFile(0); continue; }
case 'H':
case 'h': displayOut=stdout; CLEAN_RETURN(usage_advanced(programName));
+ /* Compress */
+ case 'z': operation=zom_compress; argument++; break;
+
/* Decoding */
- case 'd': decode=1; argument++; break;
+ case 'd': operation=zom_decompress; argument++; break;
/* Force stdout, even if stdout==console */
case 'c': forceStdout=1; outFileName=stdoutmark; argument++; break;
case 'C': argument++; FIO_setChecksumFlag(2); break;
/* test compressed file */
- case 't': testmode=1; decode=1; argument++; break;
+ case 't': operation=zom_test; argument++; break;
/* destination file name */
case 'o': nextArgumentIsOutFileName=1; lastCommand=1; argument++; break;
#ifndef ZSTD_NOBENCH
/* Benchmark */
- case 'b': bench=1; argument++; break;
+ case 'b': operation=zom_train; argument++; break;
/* range bench (benchmark only) */
case 'e':
#endif
/* Check if benchmark is selected */
- if (bench) {
+ if (operation==zom_bench) {
#ifndef ZSTD_NOBENCH
BMK_setNotificationLevel(displayLevel);
BMK_benchFiles(filenameTable, filenameIdx, dictFileName, cLevel, cLevelLast);
}
/* Check if dictionary builder is selected */
- if (dictBuild) {
+ if (operation==zom_train) {
#ifndef ZSTD_NODICT
ZDICT_params_t dictParams;
memset(&dictParams, 0, sizeof(dictParams));
/* Check if input/output defined as console; trigger an error in this case */
if (!strcmp(filenameTable[0], stdinmark) && IS_CONSOLE(stdin) ) CLEAN_RETURN(badusage(programName));
- if (outFileName && !strcmp(outFileName, stdoutmark) && IS_CONSOLE(stdout) && strcmp(filenameTable[0], stdinmark) && !(forceStdout && decode))
+ if (outFileName && !strcmp(outFileName, stdoutmark) && IS_CONSOLE(stdout) && strcmp(filenameTable[0], stdinmark) && !(forceStdout && (operation==zom_decompress)))
CLEAN_RETURN(badusage(programName));
/* user-selected output filename, only possible with a single file */
/* IO Stream/File */
FIO_setNotificationLevel(displayLevel);
- if (!decode) {
+ if (operation==zom_compress) {
#ifndef ZSTD_NOCOMPRESS
if ((filenameIdx==1) && outFileName)
operationResult = FIO_compressFilename(outFileName, filenameTable[0], dictFileName, cLevel);
#else
DISPLAY("Compression not supported\n");
#endif
- } else { /* decompression */
+ } else { /* decompression or test */
#ifndef ZSTD_NODECOMPRESS
- if (testmode) { outFileName=nulmark; FIO_setRemoveSrcFile(0); } /* test mode */
+ if (operation==zom_test) { outFileName=nulmark; FIO_setRemoveSrcFile(0); } /* test mode */
FIO_setMemLimit(memLimit);
if (filenameIdx==1 && outFileName)
operationResult = FIO_decompressFilename(outFileName, filenameTable[0], dictFileName);