uncompress.1p (5961B)
- '\" et
- .TH UNCOMPRESS "1P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual"
- .\"
- .SH PROLOG
- This manual page is part of the POSIX Programmer's Manual.
- The Linux implementation of this interface may differ (consult
- the corresponding Linux manual page for details of Linux behavior),
- or the interface may not be implemented on Linux.
- .\"
- .SH NAME
- uncompress
- \(em expand compressed data
- .SH SYNOPSIS
- .LP
- .nf
- uncompress \fB[\fR-cfv\fB] [\fIfile\fR...\fB]\fR
- .fi
- .SH DESCRIPTION
- The
- .IR uncompress
- utility shall restore files to their original state after they have
- been compressed using the
- .IR compress
- utility. If no files are specified, the standard input shall be
- uncompressed to the standard output. If the invoking process has
- appropriate privileges, the ownership, modes, access time, and
- modification time of the original file shall be preserved.
- .P
- This utility shall support the uncompressing of any files produced by
- the
- .IR compress
- utility on the same implementation. For files produced by
- .IR compress
- on other systems,
- .IR uncompress
- supports 9 to 14-bit compression (see
- .IR "\fIcompress\fR\^",
- .BR \-b );
- it is implementation-defined whether values of
- .BR \-b
- greater than 14 are supported.
- .SH OPTIONS
- The
- .IR uncompress
- utility shall conform to the Base Definitions volume of POSIX.1\(hy2017,
- .IR "Section 12.2" ", " "Utility Syntax Guidelines",
- except that Guideline 1 does apply since the utility name has ten letters.
- .P
- The following options shall be supported:
- .IP "\fB\-c\fP" 10
- Write to standard output; no files are changed.
- .IP "\fB\-f\fP" 10
- Do not prompt for overwriting files. Except when run in the
- background, if
- .BR \-f
- is not given the user shall be prompted as to whether an existing file
- should be overwritten. If the standard input is not a terminal and
- .BR \-f
- is not given,
- .IR uncompress
- shall write a diagnostic message to standard error and exit with a
- status greater than zero.
- .IP "\fB\-v\fP" 10
- Write messages to standard error concerning the expansion of each file.
- .SH OPERANDS
- The following operand shall be supported:
- .IP "\fIfile\fR" 10
- A pathname of a file. If
- .IR file
- already has the
- .BR .Z
- suffix specified, it shall be used as the input file and the output
- file shall be named
- .BR file
- with the
- .BR .Z
- suffix removed. Otherwise,
- .IR file
- shall be used as the name of the output file and
- .BR file
- with the
- .BR .Z
- suffix appended shall be used as the input file.
- .SH STDIN
- The standard input shall be used only if no
- .IR file
- operands are specified, or if a
- .IR file
- operand is
- .BR '\-' .
- .SH "INPUT FILES"
- Input files shall be in the format produced by the
- .IR compress
- utility.
- .SH "ENVIRONMENT VARIABLES"
- The following environment variables shall affect the execution of
- .IR uncompress :
- .IP "\fILANG\fP" 10
- Provide a default value for the internationalization variables that are
- unset or null. (See the Base Definitions volume of POSIX.1\(hy2017,
- .IR "Section 8.2" ", " "Internationalization Variables"
- for the precedence of internationalization variables used to determine
- the values of locale categories.)
- .IP "\fILC_ALL\fP" 10
- If set to a non-empty string value, override the values of all the
- other internationalization variables.
- .IP "\fILC_CTYPE\fP" 10
- Determine the locale for the interpretation of sequences of bytes of
- text data as characters (for example, single-byte as opposed to
- multi-byte characters in arguments).
- .IP "\fILC_MESSAGES\fP" 10
- .br
- Determine the locale that should be used to affect the format and
- contents of diagnostic messages written to standard error.
- .IP "\fINLSPATH\fP" 10
- Determine the location of message catalogs for the processing of
- .IR LC_MESSAGES .
- .SH "ASYNCHRONOUS EVENTS"
- Default.
- .SH STDOUT
- When there are no
- .IR file
- operands or the
- .BR \-c
- option is specified, the uncompressed output is written to standard
- output.
- .SH STDERR
- Prompts shall be written to the standard error output under the
- conditions specified in the DESCRIPTION and OPTIONS sections. The
- prompts shall contain the
- .IR file
- pathname, but their format is otherwise unspecified. Otherwise, the
- standard error output shall be used only for diagnostic messages.
- .SH "OUTPUT FILES"
- Output files are the same as the respective input files to
- .IR compress .
- .SH "EXTENDED DESCRIPTION"
- None.
- .SH "EXIT STATUS"
- The following exit values shall be returned:
- .IP "\00" 6
- Successful completion.
- .IP >0 6
- An error occurred.
- .SH "CONSEQUENCES OF ERRORS"
- The input file remains unmodified.
- .LP
- .IR "The following sections are informative."
- .SH "APPLICATION USAGE"
- The limit of 14 on the
- .IR compress
- .BR \-b
- .IR bits
- argument is to achieve portability to all systems (within the
- restrictions imposed by the lack of an explicit published file
- format). Some implementations based on 16-bit architectures cannot
- support 15 or 16-bit uncompression.
- .SH EXAMPLES
- None.
- .SH RATIONALE
- None.
- .SH "FUTURE DIRECTIONS"
- None.
- .SH "SEE ALSO"
- .IR "\fIcompress\fR\^",
- .IR "\fIzcat\fR\^"
- .P
- The Base Definitions volume of POSIX.1\(hy2017,
- .IR "Chapter 8" ", " "Environment Variables",
- .IR "Section 12.2" ", " "Utility Syntax Guidelines"
- .\"
- .SH COPYRIGHT
- Portions of this text are reprinted and reproduced in electronic form
- from IEEE Std 1003.1-2017, Standard for Information Technology
- -- Portable Operating System Interface (POSIX), The Open Group Base
- Specifications Issue 7, 2018 Edition,
- Copyright (C) 2018 by the Institute of
- Electrical and Electronics Engineers, Inc and The Open Group.
- In the event of any discrepancy between this version and the original IEEE and
- The Open Group Standard, the original IEEE and The Open Group Standard
- is the referee document. The original Standard can be obtained online at
- http://www.opengroup.org/unix/online.html .
- .PP
- Any typographical or formatting errors that appear
- in this page are most likely
- to have been introduced during the conversion of the source files to
- man page format. To report such errors, see
- https://www.kernel.org/doc/man-pages/reporting_bugs.html .