compress

NAME

compress - compress data

SYNOPSIS 

compress [-cCdf?hkKvV] [-b maxbits] [-Iinpath] [-Ooutpath] [filenames...]

DESCRIPTION

The compress(1) utility uses adaptive Lempel-Ziv coding to reduce the size of files. (The utilities gzip(1), pack(1) and zip(1) also compress data, but they use different algorithms.) The compress(1) utility reads data from the specified files or from standard input if no files are specified or if one of the files is -. If compress(1) reads standard input, it writes to standard output. If compress(1) is not writing to standard output, it replaces the file with a new file whose name has the extension .Z appended. If adding .Z makes the name longer than {NAME_MAX} bytes long, the operation fails.

If no files are specified, or the -c option is given, the compressed data is written to standard output.

If the invoking process has the appropriate privileges, compress(1) preserves the ownership, modes, access time, and modification time of the original file.

OPTIONS

-V
print Version
-d
do_decomp default = on
-v
verbose
-f
force overwrite of output file default = off
-n
no header: useful to uncompress old files
-c
cat all output to stdout default = off
-C
generate output compatible with compress 2.0.
-k
keep input file, default == kill (erase)
-K
keep output file on error, default == kill (erase)
-b maxbits
default == 16 bits, max == 16 bits
-I pathname
infile path ==
-O pathname
outfile path ==
-? | -h
help usage.

DIAGNOSTICS

The compress(1) utility exits with the following values:
0
Success.
1
An error occurred.
2
One or more of the files were not compressed because -f was not specified and the files would have increased in size.
>2
An error occurred.

NOTES

The XPG 4 specification recommends that, for portability reasons, bits not be set to a value larger than 14. Most implementations support values up to 16, but this is not guaranteed or required by any standards.

SEE ALSO

gzip(1)

gunzip(1)

pack(1)

uncompress(1)

zcat(1)

zip(1)