4.4BSD/usr/share/man/cat3/confstr.0

CONFSTR(3)                  BSD Programmer's Manual                 CONFSTR(3)

NNAAMMEE
     ccoonnffssttrr - get string-valued configurable variables

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     _s_i_z_e___t
     ccoonnffssttrr(_i_n_t _n_a_m_e, _c_h_a_r _*_b_u_f, _s_i_z_e___t _l_e_n);

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     The ccoonnffssttrr() function provides a method for applications to get configu-
     ration defined string values.

     The _n_a_m_e argument specifies the system variable to be queried.  Symbolic
     constants for each name value are found in the include file <unistd.h>.
     The _l_e_n argument specifies the size of the buffer referenced by the argu-
     ment _b_u_f. If _l_e_n is non-zero, _b_u_f is a non-null pointer, and _n_a_m_e has a
     value, up to _l_e_n - 1 bytes of the value are copied into the buffer _b_u_f.
     The copied value is always null terminated.

     The available values are as follows:

     _CS_PATH
             Return a value for the PATH environment variable that finds all
             the standard utilities.

RREETTUURRNN VVAALLUUEESS
     If the call to ccoonnffssttrr is not successful, -1 is returned and _e_r_r_n_o is set
     appropriately.  Otherwise, if the variable does not have a configuration
     defined value, 0 is returned and _e_r_r_n_o is not modified.  Otherwise, the
     buffer size needed to hold the entire configuration-defined value is re-
     turned.  If this size is greater than the argument _l_e_n, the string in _b_u_f
     was truncated.

EERRRROORRSS
     The ccoonnffssttrr function may fail and set _e_r_r_o_r for any of the errors speci-
     fied for the library functions malloc(3) and sysctl(3).

     In addition, the following errors may be reported:

     [EINVAL]      The value of the _n_a_m_e argument is invalid.

SSEEEE AALLSSOO
     sysctl(3)

HHIISSTTOORRYY
     The ccoonnffssttrr function first appeared in 4.4BSD.

4th Berkeley Distribution        June 4, 1993                                1