• NAME
• SUPPORTED PLATFORMS
• SYNOPSIS
• DESCRIPTION
• EXAMPLE
• WARNING
• GLOSSARY
• _
• a
• b
• c
• C
• d
• e
• f
• g
• h
• i
• k
• l
• m
• M
• n
• o
• p
• P
• q
• r
• s
• t
• u
• v
• x
• z
• NOTE

NAME

Config - access Perl configuration information

SUPPORTED PLATFORMS

• Linux
• Solaris
• Windows

SYNOPSIS

    use Config;
    if ($Config{'cc'} =~ /gcc/) {
        print "built by gcc\n";
    }

    use Config qw(myconfig config_sh config_vars);

    print myconfig();

    print config_sh();

    config_vars(qw(osname archname));

DESCRIPTION

The Config module contains all the information that was available to the Configure program at Perl build time (over 900 values).

Shell variables from the config.sh file (written by Configure) are stored in the readonly-variable %Config, indexed by their names.

Values stored in config.sh as 'undef' are returned as undefined values. The perl exists function can be used to check if a named variable exists.

myconfig()

Returns a textual summary of the major perl configuration values. See also -V in Switches in the perlrun manpage.

config_sh()

Returns the entire perl configuration information in the form of the original config.sh shell variable assignment script.

config_vars(@names)

Prints to STDOUT the values of the named configuration variable. Each is printed on a separate line in the form:

  name='value';

Names which are unknown are output as name='UNKNOWN';. See also -V:name in Switches in the perlrun manpage.

EXAMPLE

Here's a more sophisticated example of using %Config:

    use Config;
    use strict;

    my %sig_num;
    my @sig_name;
    unless($Config{sig_name} && $Config{sig_num}) {
        die "No sigs?";
    } else {
        my @names = split ' ', $Config{sig_name};
        @sig_num{@names} = split ' ', $Config{sig_num};
        foreach (@names) {
            $sig_name[$sig_num{$_}] ||= $_;
        }   
    }

    print "signal #17 = $sig_name[17]\n";
    if ($sig_num{ALRM}) { 
        print "SIGALRM is $sig_num{ALRM}\n";
    }

WARNING

Because this information is not stored within the perl executable itself it is possible (but unlikely) that the information does not relate to the actual perl binary which is being used to access it.

The Config module is installed into the architecture and version specific library directory ($Config{installarchlib}) and it checks the perl version number when loaded.

The values stored in config.sh may be either single-quoted or double-quoted. Double-quoted strings are handy for those cases where you need to include escape sequences in the strings. To avoid runtime variable interpolation, any $ and @ characters are replaced by \$ and \@, respectively. This isn't foolproof, of course, so don't embed \$ or \@ in double-quoted strings unless you're willing to deal with the consequences. (The slashes will end up escaped and the $ or @ will trigger variable interpolation)

GLOSSARY

Most Config variables are determined by the Configure script on platforms supported by it (which is most UNIX platforms). Some platforms have custom-made Config variables, and may thus not have some of the variables described below, or may have extraneous variables specific to that particular port. See the port specific documentation in such cases.

_

_a

From Unix.U:

This variable defines the extension used for ordinary libraries. For unix, it is .a. The . is included. Other possible values include .lib.

_exe

From Unix.U:

This variable defines the extension used for executable files. For unix it is empty. Other possible values include .exe.

_o

From Unix.U:

This variable defines the extension used for object files. For unix, it is .o. The . is included. Other possible values include .obj.

a

afs

From afs.U:

This variable is set to true if AFS (Andrew File System) is used on the system, false otherwise. It is possible to override this with a hint value or command line option, but you'd better know what you are doing.

alignbytes

From alignbytes.U:

This variable holds the number of bytes required to align a double-- or a long double when applicable. Usual values are 2, 4 and 8. The default is eight, for safety.

ansi2knr

From ansi2knr.U:

This variable is set if the user needs to run ansi2knr. Currently, this is not supported, so we just abort.

aphostname

From d_gethname.U:

This variable contains the command which can be used to compute the host name. The command is fully qualified by its absolute path, to make it safe when used by a process with super-user privileges.

api_revision

From patchlevel.U:

The three variables, api_revision, api_version, and api_subversion, specify the version of the oldest perl binary compatible with the present perl. In a full version string such as 5.6.1, api_revision is the 5. Prior to 5.5.640, the format was a floating point number, like 5.00563.

        F<perl.c>:incpush() and F<lib/lib.pm> will automatically search in

        $F<sitelib/.>. for older directories back to the limit specified
by these api_ variables.  This is only useful if you have a
perl library directory tree structured like the default one.
See C<INSTALL> for how this works.  The versioned site_perl
directory was introduced in 5.005, so that is the lowest
possible value.  The version list appropriate for the current
system is determined in F<inc_version_list.U>.

        C<XXX> To do:  Since compatibility can depend on compile time

        options (such as bincompat, longlong, F<etc.>) it should
(perhaps) be set by Configure, but currently it isn't.
Currently, we read a hard-wired value from F<patchlevel.h>.
Perhaps what we ought to do is take the hard-wired value from
F<patchlevel.h> but then modify it if the current Configure
options warrant.  F<patchlevel.h> then would use an #ifdef guard.

api_subversion

From patchlevel.U:

The three variables, api_revision, api_version, and api_subversion, specify the version of the oldest perl binary compatible with the present perl. In a full version string such as 5.6.1, api_subversion is the 1. See api_revision for full details.

api_version

From patchlevel.U:

The three variables, api_revision, api_version, and api_subversion, specify the version of the oldest perl binary compatible with the present perl. In a full version string such as 5.6.1, api_version is the 6. See api_revision for full details. As a special case, 5.5.0 is rendered in the old-style as 5.005. (In the 5.005_0x maintenance series, this was the only versioned directory in $sitelib.)

api_versionstring

From patchlevel.U:

This variable combines api_revision, api_version, and api_subversion in a format such as 5.6.1 (or 5_6_1) suitable for use as a directory name. This is filesystem dependent.

ar

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the ar program. After Configure runs, the value is reset to a plain ar and is not useful.

archlib

From archlib.U:

This variable holds the name of the directory in which the user wants to put architecture-dependent public library files for $package. It is most often a local directory such as /usr/local/lib. Programs using this variable must be prepared to deal with filename expansion.

archlibexp

From archlib.U:

This variable is the same as the archlib variable, but is filename expanded at configuration time, for convenient use.

archname64

From use64bits.U:

This variable is used for the 64-bitness part of $archname.

archname

From archname.U:

This variable is a short name to characterize the current architecture. It is used mainly to construct the default archlib.

archobjs

From Unix.U:

This variable defines any additional objects that must be linked in with the program on this architecture. On unix, it is usually empty. It is typically used to include emulations of unix calls or other facilities. For perl on OS/2, for example, this would include os2/os2.obj.

awk

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the awk program. After Configure runs, the value is reset to a plain awk and is not useful.

b

baserev

From baserev.U:

The base revision level of this package, from the .package file.

bash

From Loc.U:

This variable is defined but not used by Configure. The value is a plain '' and is not useful.

bin

From bin.U:

This variable holds the name of the directory in which the user wants to put publicly executable images for the package in question. It is most often a local directory such as /usr/local/bin. Programs using this variable must be prepared to deal with ~name substitution.

bincompat5005

From bincompat5005.U:

This variable contains y if this version of Perl should be binary-compatible with Perl 5.005.

binexp

From bin.U:

This is the same as the bin variable, but is filename expanded at configuration time, for use in your makefiles.

bison

From Loc.U:

This variable is defined but not used by Configure. The value is a plain '' and is not useful.

byacc

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the byacc program. After Configure runs, the value is reset to a plain byacc and is not useful.

byteorder

From byteorder.U:

This variable holds the byte order. In the following, larger digits indicate more significance. The variable byteorder is either 4321 on a big-endian machine, or 1234 on a little-endian, or 87654321 on a Cray ... or 3412 with weird order !

c

c

From n.U:

This variable contains the \c string if that is what causes the echo command to suppress newline. Otherwise it is null. Correct usage is $echo $n ``prompt for a question: $c''.

castflags

From d_castneg.U:

This variable contains a flag that precise difficulties the compiler has casting odd floating values to unsigned long: 0 = ok 1 = couldn't cast < 0 2 = couldn't cast >= 0x80000000 4 = couldn't cast in argument expression list

cat

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the cat program. After Configure runs, the value is reset to a plain cat and is not useful.

cc

From cc.U:

This variable holds the name of a command to execute a C compiler which can resolve multiple global references that happen to have the same name. Usual values are cc, Mcc, cc -M, and gcc.

cccdlflags

From dlsrc.U:

This variable contains any special flags that might need to be passed with cc -c to compile modules to be used to create a shared library that will be used for dynamic loading. For hpux, this should be +z. It is up to the makefile to use it.

ccdlflags

From dlsrc.U:

This variable contains any special flags that might need to be passed to cc to link with a shared library for dynamic loading. It is up to the makefile to use it. For sunos 4.1, it should be empty.

ccflags

From ccflags.U:

This variable contains any additional C compiler flags desired by the user. It is up to the Makefile to use this.

ccsymbols

From Cppsym.U:

The variable contains the symbols defined by the C compiler alone. The symbols defined by cpp or by cc when it calls cpp are not in this list, see cppsymbols and cppccsymbols. The list is a space-separated list of symbol=value tokens.

cf_by

From cf_who.U:

Login name of the person who ran the Configure script and answered the questions. This is used to tag both config.sh and config_h.SH.

cf_email

From cf_email.U:

Electronic mail address of the person who ran Configure. This can be used by units that require the user's e-mail, like MailList.U.

cf_time

From cf_who.U:

Holds the output of the date command when the configuration file was produced. This is used to tag both config.sh and config_h.SH.

charsize

From charsize.U:

This variable contains the value of the CHARSIZE symbol, which indicates to the C program how many bytes there are in a character.

chgrp

From Loc.U:

This variable is defined but not used by Configure. The value is a plain '' and is not useful.

chmod

From Loc.U:

This variable is defined but not used by Configure. The value is a plain '' and is not useful.

chown

From Loc.U:

This variable is defined but not used by Configure. The value is a plain '' and is not useful.

clocktype

From d_times.U:

This variable holds the type returned by times(). It can be long, or clock_t on BSD sites (in which case <sys/types.h> should be included).

comm

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the comm program. After Configure runs, the value is reset to a plain comm and is not useful.

compress

From Loc.U:

This variable is defined but not used by Configure. The value is a plain '' and is not useful.

C

CONFIGDOTSH

From Oldsyms.U:

This is set to true in config.sh so that a shell script sourcing config.sh can tell if it has been sourced already.

contains

From contains.U:

This variable holds the command to do a grep with a proper return status. On most sane systems it is simply grep. On insane systems it is a grep followed by a cat followed by a test. This variable is primarily for the use of other Configure units.

cp

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the cp program. After Configure runs, the value is reset to a plain cp and is not useful.

cpio

From Loc.U:

This variable is defined but not used by Configure. The value is a plain '' and is not useful.

cpp

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the cpp program. After Configure runs, the value is reset to a plain cpp and is not useful.

cpp_stuff

From cpp_stuff.U:

This variable contains an identification of the catenation mechanism used by the C preprocessor.

cppccsymbols

From Cppsym.U:

The variable contains the symbols defined by the C compiler when it calls cpp. The symbols defined by the cc alone or cpp alone are not in this list, see ccsymbols and cppsymbols. The list is a space-separated list of symbol=value tokens.

cppflags

From ccflags.U:

This variable holds the flags that will be passed to the C pre- processor. It is up to the Makefile to use it.

cpplast

From cppstdin.U:

This variable has the same functionality as cppminus, only it applies to cpprun and not cppstdin.

cppminus

From cppstdin.U:

This variable contains the second part of the string which will invoke the C preprocessor on the standard input and produce to standard output. This variable will have the value - if cppstdin needs a minus to specify standard input, otherwise the value is ``''.

cpprun

From cppstdin.U:

This variable contains the command which will invoke a C preprocessor on standard input and put the output to stdout. It is guaranteed not to be a wrapper and may be a null string if no preprocessor can be made directly available. This preprocessor might be different from the one used by the C compiler. Don't forget to append cpplast after the preprocessor options.

cppstdin

From cppstdin.U:

This variable contains the command which will invoke the C preprocessor on standard input and put the output to stdout. It is primarily used by other Configure units that ask about preprocessor symbols.

cppsymbols

From Cppsym.U:

The variable contains the symbols defined by the C preprocessor alone. The symbols defined by cc or by cc when it calls cpp are not in this list, see ccsymbols and cppccsymbols. The list is a space-separated list of symbol=value tokens.

crosscompile

From crosscompile.U:

This variable conditionally defines the CROSSCOMPILE symbol which signifies that the build process is be a cross-compilation. This is normally set by hints files or from Configure command line.

cryptlib

From d_crypt.U:

This variable holds -lcrypt or the path to a libcrypt.a archive if the crypt() function is not defined in the standard C library. It is up to the Makefile to use this.

csh

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the csh program. After Configure runs, the value is reset to a plain csh and is not useful.

d

d_access

From d_access.U:

This variable conditionally defines HAS_ACCESS if the access() system call is available to check for access permissions using real IDs.

d_accessx

From d_accessx.U:

This variable conditionally defines the HAS_ACCESSX symbol, which indicates to the C program that the accessx() routine is available.

d_alarm

From d_alarm.U:

This variable conditionally defines the HAS_ALARM symbol, which indicates to the C program that the alarm() routine is available.

d_archlib

From archlib.U:

This variable conditionally defines ARCHLIB to hold the pathname of architecture-dependent library files for $package. If $archlib is the same as $privlib, then this is set to undef.

d_atolf

From atolf.U:

This variable conditionally defines the HAS_ATOLF symbol, which indicates to the C program that the atolf() routine is available.

d_atoll

From atoll.U:

This variable conditionally defines the HAS_ATOLL symbol, which indicates to the C program that the atoll() routine is available.

d_attribut

From d_attribut.U:

This variable conditionally defines HASATTRIBUTE, which indicates the C compiler can check for function attributes, such as printf formats.

d_bcmp

From d_bcmp.U:

This variable conditionally defines the HAS_BCMP symbol if the bcmp() routine is available to compare strings.

d_bcopy

From d_bcopy.U:

This variable conditionally defines the HAS_BCOPY symbol if the bcopy() routine is available to copy strings.

d_bincompat5005

From bincompat5005.U:

This variable conditionally defines BINCOMPAT5005 so that embed.h can take special action if this version of Perl should be binary-compatible with Perl 5.005. This is impossible for builds that use features like threads and multiplicity it is always $undef for those versions.

d_bsd

From Guess.U:

This symbol conditionally defines the symbol BSD when running on a BSD system.

d_bsdgetpgrp

From d_getpgrp.U:

This variable conditionally defines USE_BSD_GETPGRP if getpgrp needs one arguments whereas USG one needs none.

d_bsdsetpgrp

From d_setpgrp.U:

This variable conditionally defines USE_BSD_SETPGRP if setpgrp needs two arguments whereas USG one needs none. See also d_setpgid for a POSIX interface.

d_bzero

From d_bzero.U:

This variable conditionally defines the HAS_BZERO symbol if the bzero() routine is available to set memory to 0.

d_casti32

From d_casti32.U:

This variable conditionally defines CASTI32, which indicates whether the C compiler can cast large floats to 32-bit ints.

d_castneg

From d_castneg.U:

This variable conditionally defines CASTNEG, which indicates wether the C compiler can cast negative float to unsigned.

d_charvspr

From d_vprintf.U:

This variable conditionally defines CHARVSPRINTF if this system has vsprintf returning type (char*). The trend seems to be to declare it as ``int vsprintf()''.

d_chown

From d_chown.U:

This variable conditionally defines the HAS_CHOWN symbol, which indicates to the C program that the chown() routine is available.

d_chroot

From d_chroot.U:

This variable conditionally defines the HAS_CHROOT symbol, which indicates to the C program that the chroot() routine is available.

d_chsize

From d_chsize.U:

This variable conditionally defines the CHSIZE symbol, which indicates to the C program that the chsize() routine is available to truncate files. You might need a -lx to get this routine.

d_closedir

From d_closedir.U:

This variable conditionally defines HAS_CLOSEDIR if closedir() is available.

d_const

From d_const.U:

This variable conditionally defines the HASCONST symbol, which indicates to the C program that this C compiler knows about the const type.

d_crypt

From d_crypt.U:

This variable conditionally defines the CRYPT symbol, which indicates to the C program that the crypt() routine is available to encrypt passwords and the like.

d_csh

From d_csh.U:

This variable conditionally defines the CSH symbol, which indicates to the C program that the C-shell exists.

d_cuserid

From d_cuserid.U:

This variable conditionally defines the HAS_CUSERID symbol, which indicates to the C program that the cuserid() routine is available to get character login names.

d_dbl_dig

From d_dbl_dig.U:

This variable conditionally defines d_dbl_dig if this system's header files provide DBL_DIG, which is the number of significant digits in a double precision number.

d_difftime

From d_difftime.U:

This variable conditionally defines the HAS_DIFFTIME symbol, which indicates to the C program that the difftime() routine is available.

d_dirnamlen

From i_dirent.U:

This variable conditionally defines DIRNAMLEN, which indicates to the C program that the length of directory entry names is provided by a d_namelen field.

d_dlerror

From d_dlerror.U:

This variable conditionally defines the HAS_DLERROR symbol, which indicates to the C program that the dlerror() routine is available.

d_dlopen

From d_dlopen.U:

This variable conditionally defines the HAS_DLOPEN symbol, which indicates to the C program that the dlopen() routine is available.

d_dlsymun

From d_dlsymun.U:

This variable conditionally defines DLSYM_NEEDS_UNDERSCORE, which indicates that we need to prepend an underscore to the symbol name before calling dlsym().

d_dosuid

From d_dosuid.U:

This variable conditionally defines the symbol DOSUID, which tells the C program that it should insert setuid emulation code on hosts which have setuid #! scripts disabled.

d_drand48proto

From d_drand48proto.U:

This variable conditionally defines the HAS_DRAND48_PROTO symbol, which indicates to the C program that the system provides a prototype for the drand48() function. Otherwise, it is up to the program to supply one.

d_dup2

From d_dup2.U:

This variable conditionally defines HAS_DUP2 if dup2() is available to duplicate file descriptors.

d_eaccess

From d_eaccess.U:

This variable conditionally defines the HAS_EACCESS symbol, which indicates to the C program that the eaccess() routine is available.

d_endgrent

From d_endgrent.U:

This variable conditionally defines the HAS_ENDGRENT symbol, which indicates to the C program that the endgrent() routine is available for sequential access of the group database.

d_endhent

From d_endhent.U:

This variable conditionally defines HAS_ENDHOSTENT if endhostent() is available to close whatever was being used for host queries.

d_endnent

From d_endnent.U:

This variable conditionally defines HAS_ENDNETENT if endnetent() is available to close whatever was being used for network queries.

d_endpent

From d_endpent.U:

This variable conditionally defines HAS_ENDPROTOENT if endprotoent() is available to close whatever was being used for protocol queries.

d_endpwent

From d_endpwent.U:

This variable conditionally defines the HAS_ENDPWENT symbol, which indicates to the C program that the endpwent() routine is available for sequential access of the passwd database.

d_endsent

From d_endsent.U:

This variable conditionally defines HAS_ENDSERVENT if endservent() is available to close whatever was being used for service queries.

d_endspent

From d_endspent.U:

This variable conditionally defines HAS_ENDSPENT if endspent() is available to finalize the scan of SysV shadow password entries.

d_eofnblk

From nblock_io.U:

This variable conditionally defines EOF_NONBLOCK if EOF can be seen when reading from a non-blocking I/O source.

d_eunice

From Guess.U:

This variable conditionally defines the symbols EUNICE and VAX, which alerts the C program that it must deal with ideosyncracies of VMS.

d_fchmod

From d_fchmod.U:

This variable conditionally defines the HAS_FCHMOD symbol, which indicates to the C program that the fchmod() routine is available to change mode of opened files.

d_fchown

From d_fchown.U:

This variable conditionally defines the HAS_FCHOWN symbol, which indicates to the C program that the fchown() routine is available to change ownership of opened files.

d_fcntl

From d_fcntl.U:

This variable conditionally defines the HAS_FCNTL symbol, and indicates whether the fcntl() function exists

d_fd_macros

From d_fd_set.U:

This variable contains the eventual value of the HAS_FD_MACROS symbol, which indicates if your C compiler knows about the macros which manipulate an fd_set.

d_fd_set

From d_fd_set.U:

This variable contains the eventual value of the HAS_FD_SET symbol, which indicates if your C compiler knows about the fd_set typedef.

d_fds_bits

From d_fd_set.U:

This variable contains the eventual value of the HAS_FDS_BITS symbol, which indicates if your fd_set typedef contains the fds_bits member. If you have an fd_set typedef, but the dweebs who installed it did a half-fast job and neglected to provide the macros to manipulate an fd_set, HAS_FDS_BITS will let us know how to fix the gaffe.

d_fgetpos

From d_fgetpos.U:

This variable conditionally defines HAS_FGETPOS if fgetpos() is available to get the file position indicator.

d_flexfnam

From d_flexfnam.U:

This variable conditionally defines the FLEXFILENAMES symbol, which indicates that the system supports filenames longer than 14 characters.

d_flock

From d_flock.U:

This variable conditionally defines HAS_FLOCK if flock() is available to do file locking.

d_fork

From d_fork.U:

This variable conditionally defines the HAS_FORK symbol, which indicates to the C program that the fork() routine is available.

d_fpathconf

From d_pathconf.U:

This variable conditionally defines the HAS_FPATHCONF symbol, which indicates to the C program that the pathconf() routine is available to determine file-system related limits and options associated with a given open file descriptor.

d_fpos64_t

From d_fpos64_t.U:

This symbol will be defined if the C compiler supports fpos64_t.

d_fs_data_s

From d_fs_data_s.U:

This variable conditionally defines the HAS_STRUCT_FS_DATA symbol, which indicates that the struct fs_data is supported.

d_fseeko

From d_fseeko.U:

This variable conditionally defines the HAS_FSEEKO symbol, which indicates to the C program that the fseeko() routine is available.

d_fsetpos

From d_fsetpos.U:

This variable conditionally defines HAS_FSETPOS if fsetpos() is available to set the file position indicator.

d_fstatfs

From d_fstatfs.U:

This variable conditionally defines the HAS_FSTATFS symbol, which indicates to the C program that the fstatfs() routine is available.

d_fstatvfs

From d_statvfs.U:

This variable conditionally defines the HAS_FSTATVFS symbol, which indicates to the C program that the fstatvfs() routine is available.

d_ftello

From d_ftello.U:

This variable conditionally defines the HAS_FTELLO symbol, which indicates to the C program that the ftello() routine is available.

d_ftime

From d_ftime.U:

This variable conditionally defines the HAS_FTIME symbol, which indicates that the ftime() routine exists. The ftime() routine is basically a sub-second accuracy clock.

d_Gconvert

From d_gconvert.U:

This variable holds what Gconvert is defined as to convert floating point numbers into strings. It could be gconvert or a more complex macro emulating gconvert with gcvt() or sprintf. Possible values are: d_Gconvert=gconvert((x),(n),(t),(b)) d_Gconvert=gcvt((x),(n),(b)) d_Gconvert=sprintf((b),%.*g,(n),(x))

d_getcwd

From d_getcwd.U:

This variable conditionally defines the HAS_GETCWD symbol, which indicates to the C program that the getcwd() routine is available to get the current working directory.

d_getfsstat

From d_getfsstat.U:

This variable conditionally defines the HAS_GETFSSTAT symbol, which indicates to the C program that the getfsstat() routine is available.

d_getgrent

From d_getgrent.U:

This variable conditionally defines the HAS_GETGRENT symbol, which indicates to the C program that the getgrent() routine is available for sequential access of the group database.

d_getgrps

From d_getgrps.U:

This variable conditionally defines the HAS_GETGROUPS symbol, which indicates to the C program that the getgroups() routine is available to get the list of process groups.

d_gethbyaddr

From d_gethbyad.U:

This variable conditionally defines the HAS_GETHOSTBYADDR symbol, which indicates to the C program that the gethostbyaddr() routine is available to look up hosts by their IP addresses.

d_gethbyname

From d_gethbynm.U:

This variable conditionally defines the HAS_GETHOSTBYNAME symbol, which indicates to the C program that the gethostbyname() routine is available to look up host names in some data base or other.

d_gethent

From d_gethent.U:

This variable conditionally defines HAS_GETHOSTENT if gethostent() is available to look up host names in some data base or another.

d_gethname

From d_gethname.U:

This variable conditionally defines the HAS_GETHOSTNAME symbol, which indicates to the C program that the gethostname() routine may be used to derive the host name.

d_gethostprotos

From d_gethostprotos.U:

This variable conditionally defines the HAS_GETHOST_PROTOS symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various gethost*() functions. See also netdbtype.U for probing for various netdb types.

d_getlogin

From d_getlogin.U:

This variable conditionally defines the HAS_GETLOGIN symbol, which indicates to the C program that the getlogin() routine is available to get the login name.

d_getmnt

From d_getmnt.U:

This variable conditionally defines the HAS_GETMNT symbol, which indicates to the C program that the getmnt() routine is available to retrieve one or more mount info blocks by filename.

d_getmntent

From d_getmntent.U:

This variable conditionally defines the HAS_GETMNTENT symbol, which indicates to the C program that the getmntent() routine is available to iterate through mounted files to get their mount info.

d_getnbyaddr

From d_getnbyad.U:

This variable conditionally defines the HAS_GETNETBYADDR symbol, which indicates to the C program that the getnetbyaddr() routine is available to look up networks by their IP addresses.

d_getnbyname

From d_getnbynm.U:

This variable conditionally defines the HAS_GETNETBYNAME symbol, which indicates to the C program that the getnetbyname() routine is available to look up networks by their names.

d_getnent

From d_getnent.U:

This variable conditionally defines HAS_GETNETENT if getnetent() is available to look up network names in some data base or another.

d_getnetprotos

From d_getnetprotos.U:

This variable conditionally defines the HAS_GETNET_PROTOS symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various getnet*() functions. See also netdbtype.U for probing for various netdb types.

d_getpbyname

From d_getprotby.U:

This variable conditionally defines the HAS_GETPROTOBYNAME symbol, which indicates to the C program that the getprotobyname() routine is available to look up protocols by their name.

d_getpbynumber

From d_getprotby.U:

This variable conditionally defines the HAS_GETPROTOBYNUMBER symbol, which indicates to the C program that the getprotobynumber() routine is available to look up protocols by their number.

d_getpent

From d_getpent.U:

This variable conditionally defines HAS_GETPROTOENT if getprotoent() is available to look up protocols in some data base or another.

d_getpgid

From d_getpgid.U:

This variable conditionally defines the HAS_GETPGID symbol, which indicates to the C program that the getpgid(pid) function is available to get the process group id.

d_getpgrp2

From d_getpgrp2.U:

This variable conditionally defines the HAS_GETPGRP2 symbol, which indicates to the C program that the getpgrp2() (as in DG/UX) routine is available to get the current process group.

d_getpgrp

From d_getpgrp.U:

This variable conditionally defines HAS_GETPGRP if getpgrp() is available to get the current process group.

d_getppid

From d_getppid.U:

This variable conditionally defines the HAS_GETPPID symbol, which indicates to the C program that the getppid() routine is available to get the parent process ID.

d_getprior

From d_getprior.U:

This variable conditionally defines HAS_GETPRIORITY if getpriority() is available to get a process's priority.

d_getprotoprotos

From d_getprotoprotos.U:

This variable conditionally defines the HAS_GETPROTO_PROTOS symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various getproto*() functions. See also netdbtype.U for probing for various netdb types.

d_getpwent

From d_getpwent.U:

This variable conditionally defines the HAS_GETPWENT symbol, which indicates to the C program that the getpwent() routine is available for sequential access of the passwd database.

d_getsbyname

From d_getsrvby.U:

This variable conditionally defines the HAS_GETSERVBYNAME symbol, which indicates to the C program that the getservbyname() routine is available to look up services by their name.

d_getsbyport

From d_getsrvby.U:

This variable conditionally defines the HAS_GETSERVBYPORT symbol, which indicates to the C program that the getservbyport() routine is available to look up services by their port.

d_getsent

From d_getsent.U:

This variable conditionally defines HAS_GETSERVENT if getservent() is available to look up network services in some data base or another.

d_getservprotos

From d_getservprotos.U:

This variable conditionally defines the HAS_GETSERV_PROTOS symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various getserv*() functions. See also netdbtype.U for probing for various netdb types.

d_getspent

From d_getspent.U:

This variable conditionally defines HAS_GETSPENT if getspent() is available to retrieve SysV shadow password entries sequentially.

d_getspnam

From d_getspnam.U:

This variable conditionally defines HAS_GETSPNAM if getspnam() is available to retrieve SysV shadow password entries by name.

d_gettimeod

From d_ftime.U:

This variable conditionally defines the HAS_GETTIMEOFDAY symbol, which indicates that the gettimeofday() system call exists (to obtain a sub-second accuracy clock). You should probably include <sys/resource.h>.

d_gnulibc

From d_gnulibc.U:

Defined if we're dealing with the GNU C Library.

d_grpasswd

From i_grp.U:

This variable conditionally defines GRPASSWD, which indicates that struct group in <grp.h> contains gr_passwd.

d_hasmntopt

From d_hasmntopt.U:

This variable conditionally defines the HAS_HASMNTOPT symbol, which indicates to the C program that the hasmntopt() routine is available to query the mount options of file systems.

d_htonl

From d_htonl.U:

This variable conditionally defines HAS_HTONL if htonl() and its friends are available to do network order byte swapping.

d_iconv

From d_iconv.U:

This variable conditionally defines the HAS_ICONV symbol, which indicates to the C program that the iconv() routine is available.

d_index

From d_strchr.U:

This variable conditionally defines HAS_INDEX if index() and rindex() are available for string searching.

d_inetaton

From d_inetaton.U:

This variable conditionally defines the HAS_INET_ATON symbol, which indicates to the C program that the inet_aton() function is available to parse IP address dotted-quad strings.

d_int64_t

From d_int64_t.U:

This symbol will be defined if the C compiler supports int64_t.

d_isascii

From d_isascii.U:

This variable conditionally defines the HAS_ISASCII constant, which indicates to the C program that isascii() is available.

d_killpg

From d_killpg.U:

This variable conditionally defines the HAS_KILLPG symbol, which indicates to the C program that the killpg() routine is available to kill process groups.

d_lchown

From d_lchown.U:

This variable conditionally defines the HAS_LCHOWN symbol, which indicates to the C program that the lchown() routine is available to operate on a symbolic link (instead of following the link).

d_ldbl_dig

From d_ldbl_dig.U:

This variable conditionally defines d_ldbl_dig if this system's header files provide LDBL_DIG, which is the number of significant digits in a long double precision number.

d_link

From d_link.U:

This variable conditionally defines HAS_LINK if link() is available to create hard links.

d_locconv

From d_locconv.U:

This variable conditionally defines HAS_LOCALECONV if localeconv() is available for numeric and monetary formatting conventions.

d_lockf

From d_lockf.U:

This variable conditionally defines HAS_LOCKF if lockf() is available to do file locking.

d_longdbl

From d_longdbl.U:

This variable conditionally defines HAS_LONG_DOUBLE if the long double type is supported.

d_longlong

From d_longlong.U:

This variable conditionally defines HAS_LONG_LONG if the long long type is supported.

d_lseekproto

From d_lseekproto.U:

This variable conditionally defines the HAS_LSEEK_PROTO symbol, which indicates to the C program that the system provides a prototype for the lseek() function. Otherwise, it is up to the program to supply one.

d_lstat

From d_lstat.U:

This variable conditionally defines HAS_LSTAT if lstat() is available to do file stats on symbolic links.

d_madvise

From d_madvise.U:

This variable conditionally defines HAS_MADVISE if madvise() is available to map a file into memory.

d_mblen

From d_mblen.U:

This variable conditionally defines the HAS_MBLEN symbol, which indicates to the C program that the mblen() routine is available to find the number of bytes in a multibye character.

d_mbstowcs

From d_mbstowcs.U:

This variable conditionally defines the HAS_MBSTOWCS symbol, which indicates to the C program that the mbstowcs() routine is available to convert a multibyte string into a wide character string.

d_mbtowc

From d_mbtowc.U:

This variable conditionally defines the HAS_MBTOWC symbol, which indicates to the C program that the mbtowc() routine is available to convert multibyte to a wide character.

d_memchr

From d_memchr.U:

This variable conditionally defines the HAS_MEMCHR symbol,