UNCOMPRESS(1)              POSIX Programmer's Manual             UNCOMPRESS(1)



PPRROOLLOOGG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.

NNAAMMEE
       uncompress -- expand compressed data

SSYYNNOOPPSSIISS
       uncompress [[-cfv]] [[_f_i_l_e...]]

DDEESSCCRRIIPPTTIIOONN
       The _u_n_c_o_m_p_r_e_s_s utility shall restore files to their original state
       after they have been compressed using the _c_o_m_p_r_e_s_s 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.

       This utility shall support the uncompressing of any files produced by
       the _c_o_m_p_r_e_s_s utility on the same implementation. For files produced by
       _c_o_m_p_r_e_s_s on other systems, _u_n_c_o_m_p_r_e_s_s supports 9 to 14-bit compression
       (see _c_o_m_p_r_e_s_s, --bb); it is implementation-defined whether values of --bb
       greater than 14 are supported.

OOPPTTIIOONNSS
       The _u_n_c_o_m_p_r_e_s_s utility shall conform to the Base Definitions volume of
       POSIX.1-2017, _S_e_c_t_i_o_n _1_2_._2, _U_t_i_l_i_t_y _S_y_n_t_a_x _G_u_i_d_e_l_i_n_e_s, except that
       Guideline 1 does apply since the utility name has ten letters.

       The following options shall be supported:

       --cc        Write to standard output; no files are changed.

       --ff        Do not prompt for overwriting files. Except when run in the
                 background, if --ff 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 --ff is not given,
                 _u_n_c_o_m_p_r_e_s_s shall write a diagnostic message to standard error
                 and exit with a status greater than zero.

       --vv        Write messages to standard error concerning the expansion of
                 each file.

OOPPEERRAANNDDSS
       The following operand shall be supported:

       _f_i_l_e      A pathname of a file. If _f_i_l_e already has the ..ZZ suffix
                 specified, it shall be used as the input file and the output
                 file shall be named ffiillee with the ..ZZ suffix removed.
                 Otherwise, _f_i_l_e shall be used as the name of the output file
                 and ffiillee with the ..ZZ suffix appended shall be used as the
                 input file.

SSTTDDIINN
       The standard input shall be used only if no _f_i_l_e operands are
       specified, or if a _f_i_l_e operand is ''--''.

IINNPPUUTT FFIILLEESS
       Input files shall be in the format produced by the _c_o_m_p_r_e_s_s utility.

EENNVVIIRROONNMMEENNTT VVAARRIIAABBLLEESS
       The following environment variables shall affect the execution of
       _u_n_c_o_m_p_r_e_s_s:

       _L_A_N_G      Provide a default value for the internationalization
                 variables that are unset or null. (See the Base Definitions
                 volume of POSIX.1-2017, _S_e_c_t_i_o_n _8_._2, _I_n_t_e_r_n_a_t_i_o_n_a_l_i_z_a_t_i_o_n
                 _V_a_r_i_a_b_l_e_s for the precedence of internationalization
                 variables used to determine the values of locale categories.)

       _L_C___A_L_L    If set to a non-empty string value, override the values of
                 all the other internationalization variables.

       _L_C___C_T_Y_P_E  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).

       _L_C___M_E_S_S_A_G_E_S
                 Determine the locale that should be used to affect the format
                 and contents of diagnostic messages written to standard
                 error.

       _N_L_S_P_A_T_H   Determine the location of message catalogs for the processing
                 of _L_C___M_E_S_S_A_G_E_S.

AASSYYNNCCHHRROONNOOUUSS EEVVEENNTTSS
       Default.

SSTTDDOOUUTT
       When there are no _f_i_l_e operands or the --cc option is specified, the
       uncompressed output is written to standard output.

SSTTDDEERRRR
       Prompts shall be written to the standard error output under the
       conditions specified in the DESCRIPTION and OPTIONS sections. The
       prompts shall contain the _f_i_l_e pathname, but their format is otherwise
       unspecified. Otherwise, the standard error output shall be used only
       for diagnostic messages.

OOUUTTPPUUTT FFIILLEESS
       Output files are the same as the respective input files to _c_o_m_p_r_e_s_s.

EEXXTTEENNDDEEDD DDEESSCCRRIIPPTTIIOONN
       None.

EEXXIITT SSTTAATTUUSS
       The following exit values shall be returned:

        0    Successful completion.

       >0    An error occurred.

CCOONNSSEEQQUUEENNCCEESS OOFF EERRRROORRSS
       The input file remains unmodified.

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

AAPPPPLLIICCAATTIIOONN UUSSAAGGEE
       The limit of 14 on the _c_o_m_p_r_e_s_s --bb _b_i_t_s 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.

EEXXAAMMPPLLEESS
       None.

RRAATTIIOONNAALLEE
       None.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       _c_o_m_p_r_e_s_s, _z_c_a_t

       The Base Definitions volume of POSIX.1-2017, _C_h_a_p_t_e_r _8, _E_n_v_i_r_o_n_m_e_n_t
       _V_a_r_i_a_b_l_e_s, _S_e_c_t_i_o_n _1_2_._2, _U_t_i_l_i_t_y _S_y_n_t_a_x _G_u_i_d_e_l_i_n_e_s

CCOOPPYYRRIIGGHHTT
       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 .

       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 .



IEEE/The Open Group                  2017                        UNCOMPRESS(1)
