iOS Manual Pages

This document is a Mac OS X manual page. Manual pages are a command-line technology for providing documentation. You can view these manual pages locally using the man(1) command. These manual pages come from many different sources, and thus, have a variety of writing styles.

For more information about the manual page format, see the manual page for manpages(5).

CONFSTR(3)               BSD Library Functions Manual               CONFSTR(3)

NAME
     confstr -- get string-valued configurable variables

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <unistd.h>

     size_t
     confstr(int name, char *buf, size_t len);

DESCRIPTION
     This interface is specified by POSIX.  A more flexible (but non-portable)
     interface is provided by sysctl(3).

     The confstr() function provides a method for applications to get configu-ration configuration
     ration defined string values.  Shell programmers needing access to these
     parameters should use the getconf(1) utility.

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

RETURN VALUES
     If the call to confstr() is not successful, 0 is returned and errno is
     set appropriately.  Otherwise, if the variable does not have a configura-tion configuration
     tion defined value, 0 is returned and errno is not modified.  Otherwise,
     the buffer size needed to hold the entire configuration-defined value is
     returned.  If this size is greater than the argument len, the string in
     buf was truncated.

ERRORS
     The confstr() function may fail and set errno for any of the errors spec-ified specified
     ified for the library functions malloc(3) and sysctl(3).

     In addition, the following errors may be reported:

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

LEGACY ERRORS
     If the call to confstr() is not successful, -1 (rather than 0) is
     returned and errno is set appropriately.

SEE ALSO
     getconf(1), pathconf(2), sysconf(3), sysctl(3)

HISTORY
     The confstr() function first appeared in 4.4BSD.

BSD                              June 18, 2001                             BSD