ULIMIT(1)                  POSIX Programmer's Manual                 ULIMIT(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
       ulimit -- set or report file size limit

SSYYNNOOPPSSIISS
       ulimit [[-f]] [[_b_l_o_c_k_s]]

DDEESSCCRRIIPPTTIIOONN
       The _u_l_i_m_i_t utility shall set or report the file-size writing limit
       imposed on files written by the shell and its child processes (files of
       any size may be read). Only a process with appropriate privileges can
       increase the limit.

OOPPTTIIOONNSS
       The _u_l_i_m_i_t 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.

       The following option shall be supported:

       --ff        Set (or report, if no _b_l_o_c_k_s operand is present), the file
                 size limit in blocks. The --ff option shall also be the default
                 case.

OOPPEERRAANNDDSS
       The following operand shall be supported:

       _b_l_o_c_k_s    The number of 512-byte blocks to use as the new file size
                 limit.

SSTTDDIINN
       Not used.

IINNPPUUTT FFIILLEESS
       None.

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

       _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
       The standard output shall be used when no _b_l_o_c_k_s operand is present. If
       the current number of blocks is limited, the number of blocks in the
       current limit shall be written in the following format:


           "%d\n", <_n_u_m_b_e_r _o_f _5_1_2_-_b_y_t_e _b_l_o_c_k_s>

       If there is no current limit on the number of blocks, in the POSIX
       locale the following format shall be used:


           "unlimited\n"

SSTTDDEERRRR
       The standard error shall be used only for diagnostic messages.

OOUUTTPPUUTT FFIILLEESS
       None.

EEXXTTEENNDDEEDD DDEESSCCRRIIPPTTIIOONN
       None.

EEXXIITT SSTTAATTUUSS
       The following exit values shall be returned:

        0    Successful completion.

       >0    A request for a higher limit was rejected or an error occurred.

CCOONNSSEEQQUUEENNCCEESS OOFF EERRRROORRSS
       Default.

       _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
       Since _u_l_i_m_i_t affects the current shell execution environment, it is
       always provided as a shell regular built-in. If it is called in a
       separate utility execution environment, such as one of the following:


           nohup ulimit -f 10000
           env ulimit 10000

       it does not affect the file size limit of the caller's environment.

       Once a limit has been decreased by a process, it cannot be increased
       (unless appropriate privileges are involved), even back to the original
       system limit.

EEXXAAMMPPLLEESS
       Set the file size limit to 51200 bytes:


           ulimit -f 100

RRAATTIIOONNAALLEE
       None.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       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

       The System Interfaces volume of POSIX.1-2017, _u_l_i_m_i_t()

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                            ULIMIT(1)
