GNU libiberty

Introduction

The libiberty library is a collection of subroutines used by various GNU programs. It is available under the Library General Public License; for more information, see Library Copying.

This edition accompanies GCC 3, September 2001.

• Using: How to use libiberty in your code.
• Overview: Overview of available function groups.
• Functions: Available functions, macros, and global variables.
• Obstacks: Object Stacks.
• Licenses: The various licenses under which libiberty sources are distributed.
• Index: Index of functions and categories.

1 Using

To date, libiberty is generally not installed on its own. It has evolved over years but does not have its own version number nor release schedule.

Possibly the easiest way to use libiberty in your projects is to drop the libiberty code into your project's sources, and to build the library along with your own sources; the library would then be linked in at the end. This prevents any possible version mismatches with other copies of libiberty elsewhere on the system.

Passing --enable-install-libiberty to the configure script when building libiberty causes the header files and archive library to be installed when make install is run. This option also takes an (optional) argument to specify the installation location, in the same manner as --prefix.

For your own projects, an approach which offers stability and flexibility is to include libiberty with your code, but allow the end user to optionally choose to use a previously-installed version instead. In this way the user may choose (for example) to install libiberty as part of GCC, and use that version for all software built with that compiler. (This approach has proven useful with software using the GNU readline library.)

Making use of libiberty code usually requires that you include one or more header files from the libiberty distribution. (They will be named as necessary in the function descriptions.) At link time, you will need to add -liberty to your link command invocation.

2 Overview

Functions contained in libiberty can be divided into three general categories.

• Supplemental Functions: Providing functions which don't exist on older operating systems.
• Replacement Functions: These functions are sometimes buggy or unpredictable on some operating systems.
• Extensions: Functions which provide useful extensions or safety wrappers around existing code.

2.1 Supplemental Functions

Certain operating systems do not provide functions which have since become standardized, or at least common. For example, the Single Unix Specification Version 2 requires that the basename function be provided, but an OS which predates that specification might not have this function. This should not prevent well-written code from running on such a system.

Similarly, some functions exist only among a particular “flavor” or “family” of operating systems. As an example, the bzero function is often not present on systems outside the BSD-derived family of systems.

Many such functions are provided in libiberty. They are quickly listed here with little description, as systems which lack them become less and less common. Each function foo is implemented in foo.c but not declared in any libiberty header file; more comments and caveats for each function's implementation are often available in the source file. Generally, the function can simply be declared as extern.

2.2 Replacement Functions

Some functions have extremely limited implementations on different platforms. Other functions are tedious to use correctly; for example, proper use of malloc calls for the return value to be checked and appropriate action taken if memory has been exhausted. A group of “replacement functions” is available in libiberty to address these issues for some of the most commonly used subroutines.

All of these functions are declared in the libiberty.h header file. Many of the implementations will use preprocessor macros set by GNU Autoconf, if you decide to make use of that program. Some of these functions may call one another.

• Memory Allocation: Testing and handling failed memory requests automatically.
• Exit Handlers: Calling routines on program exit.
• Error Reporting: Mapping errno and signal numbers to more useful string formats.

2.2.1 Memory Allocation

The functions beginning with the letter `x' are wrappers around standard functions; the functions provided by the system environment are called and their results checked before the results are passed back to client code. If the standard functions fail, these wrappers will terminate the program. Thus, these versions can be used with impunity.

2.2.2 Exit Handlers

The existence and implementation of the atexit routine varies amongst the flavors of Unix. libiberty provides an unvarying dependable implementation via xatexit and xexit.

2.2.3 Error Reporting

These are a set of routines to facilitate programming with the system errno interface. The libiberty source file strerror.c contains a good deal of documentation for these functions.

2.3 Extensions

libiberty includes additional functionality above and beyond standard functions, which has proven generically useful in GNU programs, such as obstacks and regex. These functions are often copied from other projects as they gain popularity, and are included here to provide a central location from which to use, maintain, and distribute them.

• Obstacks: Stacks of arbitrary objects.

3 Obstacks

An obstack is a pool of memory containing a stack of objects. You can create any number of separate obstacks, and then allocate objects in specified obstacks. Within each obstack, the last object allocated must always be the first one freed, but distinct obstacks are independent of each other.

Aside from this one constraint of order of freeing, obstacks are totally general: an obstack can contain any number of objects of any size. They are implemented with macros, so allocation is usually very fast as long as the objects are usually small. And the only space overhead per object is the padding needed to start each object on a suitable boundary.

• Creating Obstacks: How to declare an obstack in your program.
• Preparing for Obstacks: Preparations needed before you can use obstacks.
• Allocation in an Obstack: Allocating objects in an obstack.
• Freeing Obstack Objects: Freeing objects in an obstack.
• Obstack Functions: The obstack functions are both functions and macros.
• Growing Objects: Making an object bigger by stages.
• Extra Fast Growing: Extra-high-efficiency (though more complicated) growing objects.
• Status of an Obstack: Inquiries about the status of an obstack.
• Obstacks Data Alignment: Controlling alignment of objects in obstacks.
• Obstack Chunks: How obstacks obtain and release chunks; efficiency considerations.
• Summary of Obstacks

3.1 Creating Obstacks

The utilities for manipulating obstacks are declared in the header file obstack.h.

You can declare variables of type struct obstack and use them as obstacks, or you can allocate obstacks dynamically like any other kind of object. Dynamic allocation of obstacks allows your program to have a variable number of different stacks. (You can even allocate an obstack structure in another obstack, but this is rarely useful.)

All the functions that work with obstacks require you to specify which obstack to use. You do this with a pointer of type struct obstack *. In the following, we often say “an obstack” when strictly speaking the object at hand is such a pointer.

The objects in the obstack are packed into large blocks called chunks. The struct obstack structure points to a chain of the chunks currently in use.

The obstack library obtains a new chunk whenever you allocate an object that won't fit in the previous chunk. Since the obstack library manages chunks automatically, you don't need to pay much attention to them, but you do need to supply a function which the obstack library should use to get a chunk. Usually you supply a function which uses malloc directly or indirectly. You must also supply a function to free a chunk. These matters are described in the following section.

3.2 Preparing for Using Obstacks

Each source file in which you plan to use the obstack functions must include the header file obstack.h, like this:

     #include <obstack.h>

Also, if the source file uses the macro obstack_init, it must declare or define two functions or macros that will be called by the obstack library. One, obstack_chunk_alloc, is used to allocate the chunks of memory into which objects are packed. The other, obstack_chunk_free, is used to return chunks when the objects in them are freed. These macros should appear before any use of obstacks in the source file.

Usually these are defined to use malloc via the intermediary xmalloc (see Unconstrained Allocation). This is done with the following pair of macro definitions:

     #define obstack_chunk_alloc xmalloc
     #define obstack_chunk_free free

Though the memory you get using obstacks really comes from malloc, using obstacks is faster because malloc is called less often, for larger blocks of memory. See Obstack Chunks, for full details.

At run time, before the program can use a struct obstack object as an obstack, it must initialize the obstack by calling obstack_init.

Here are two examples of how to allocate the space for an obstack and initialize it. First, an obstack that is a static variable:

     static struct obstack myobstack;
     ...
     obstack_init (&myobstack);

Second, an obstack that is itself dynamically allocated:

     struct obstack *myobstack_ptr
       = (struct obstack *) xmalloc (sizeof (struct obstack));
     
     obstack_init (myobstack_ptr);

3.3 Allocation in an Obstack

The most direct way to allocate an object in an obstack is with obstack_alloc, which is invoked almost like malloc.

For example, here is a function that allocates a copy of a string str in a specific obstack, which is in the variable string_obstack:

     struct obstack string_obstack;
     
     char *
     copystring (char *string)
     {
       size_t len = strlen (string) + 1;
       char *s = (char *) obstack_alloc (&string_obstack, len);
       memcpy (s, string, len);
       return s;
     }

To allocate a block with specified contents, use the function obstack_copy, declared like this:

The obstack_copy0 function is convenient for copying a sequence of characters into an obstack as a null-terminated string. Here is an example of its use:

     char *
     obstack_savestring (char *addr, int size)
     {
       return obstack_copy0 (&myobstack, addr, size);
     }

Contrast this with the previous example of savestring using malloc (see Basic Allocation).

3.4 Freeing Objects in an Obstack

To free an object allocated in an obstack, use the function obstack_free. Since the obstack is a stack of objects, freeing one object automatically frees all other objects allocated more recently in the same obstack.

Note that if object is a null pointer, the result is an uninitialized obstack. To free all memory in an obstack but leave it valid for further allocation, call obstack_free with the address of the first object allocated on the obstack:

     obstack_free (obstack_ptr, first_object_allocated_ptr);

Recall that the objects in an obstack are grouped into chunks. When all the objects in a chunk become free, the obstack library automatically frees the chunk (see Preparing for Obstacks). Then other obstacks, or non-obstack allocation, can reuse the space of the chunk.

3.5 Obstack Functions and Macros

The interfaces for using obstacks may be defined either as functions or as macros, depending on the compiler. The obstack facility works with all C compilers, including both ISO C and traditional C, but there are precautions you must take if you plan to use compilers other than GNU C.

If you are using an old-fashioned non-ISO C compiler, all the obstack “functions” are actually defined only as macros. You can call these macros like functions, but you cannot use them in any other way (for example, you cannot take their address).

Calling the macros requires a special precaution: namely, the first operand (the obstack pointer) may not contain any side effects, because it may be computed more than once. For example, if you write this:

     obstack_alloc (get_obstack (), 4);

you will find that get_obstack may be called several times. If you use *obstack_list_ptr++ as the obstack pointer argument, you will get very strange results since the incrementation may occur several times.

In ISO C, each function has both a macro definition and a function definition. The function definition is used if you take the address of the function without calling it. An ordinary call uses the macro definition by default, but you can request the function definition instead by writing the function name in parentheses, as shown here:

     char *x;
     void *(*funcp) ();
     /* Use the macro.  */
     x = (char *) obstack_alloc (obptr, size);
     /* Call the function.  */
     x = (char *) (obstack_alloc) (obptr, size);
     /* Take the address of the function.  */
     funcp = obstack_alloc;

This is the same situation that exists in ISO C for the standard library functions. See Macro Definitions.

Warning: When you do use the macros, you must observe the precaution of avoiding side effects in the first operand, even in ISO C.

If you use the GNU C compiler, this precaution is not necessary, because various language extensions in GNU C permit defining the macros so as to compute each argument only once.

3.6 Growing Objects

Because memory in obstack chunks is used sequentially, it is possible to build up an object step by step, adding one or more bytes at a time to the end of the object. With this technique, you do not need to know how much data you will put in the object until you come to the end of it. We call this the technique of growing objects. The special functions for adding data to the growing object are described in this section.

You don't need to do anything special when you start to grow an object. Using one of the functions to add data to the object automatically starts it. However, it is necessary to say explicitly when the object is finished. This is done with the function obstack_finish.

The actual address of the object thus built up is not known until the object is finished. Until then, it always remains possible that you will add so much data that the object must be copied into a new chunk.

While the obstack is in use for a growing object, you cannot use it for ordinary allocation of another object. If you try to do so, the space already added to the growing object will become part of the other object.

When you build an object by growing it, you will probably need to know afterward how long it became. You need not keep track of this as you grow the object, because you can find out the length from the obstack just before finishing the object with the function obstack_object_size, declared as follows:

If you have started growing an object and wish to cancel it, you should finish it and then free it, like this:

     obstack_free (obstack_ptr, obstack_finish (obstack_ptr));

This has no effect if no object was growing.

You can use obstack_blank with a negative size argument to make the current object smaller. Just don't try to shrink it beyond zero length—there's no telling what will happen if you do that.

3.7 Extra Fast Growing Objects

The usual functions for growing objects incur overhead for checking whether there is room for the new growth in the current chunk. If you are frequently constructing objects in small steps of growth, this overhead can be significant.

You can reduce the overhead by using special “fast growth” functions that grow the object without checking. In order to have a robust program, you must do the checking yourself. If you do this checking in the simplest way each time you are about to add data to the object, you have not saved anything, because that is what the ordinary growth functions do. But if you can arrange to check less often, or check more efficiently, then you make the program faster.

The function obstack_room returns the amount of room available in the current chunk. It is declared as follows:

While you know there is room, you can use these fast growth functions for adding data to a growing object:

When you check for space using obstack_room and there is not enough room for what you want to add, the fast growth functions are not safe. In this case, simply use the corresponding ordinary growth function instead. Very soon this will copy the object to a new chunk; then there will be lots of room available again.

So, each time you use an ordinary growth function, check afterward for sufficient space using obstack_room. Once the object is copied to a new chunk, there will be plenty of space again, so the program will start using the fast growth functions again.

Here is an example:

     void
     add_string (struct obstack *obstack, const char *ptr, int len)
     {
       while (len > 0)
         {
           int room = obstack_room (obstack);
           if (room == 0)
             {
               /* Not enough room. Add one character slowly,
                  which may copy to a new chunk and make room.  */
               obstack_1grow (obstack, *ptr++);
               len--;
             }
           else
             {
               if (room > len)
                 room = len;
               /* Add fast as much as we have room for. */
               len -= room;
               while (room-- > 0)
                 obstack_1grow_fast (obstack, *ptr++);
             }
         }
     }

3.8 Status of an Obstack

Here are functions that provide information on the current status of allocation in an obstack. You can use them to learn about an object while still growing it.

3.9 Alignment of Data in Obstacks

Each obstack has an alignment boundary; each object allocated in the obstack automatically starts on an address that is a multiple of the specified boundary. By default, this boundary is 4 bytes.

To access an obstack's alignment boundary, use the macro obstack_alignment_mask, whose function prototype looks like this:

Note that a change in alignment mask does not take effect until after the next time an object is allocated or finished in the obstack. If you are not growing an object, you can make the new alignment mask take effect immediately by calling obstack_finish. This will finish a zero-length object and then do proper alignment for the next object.

3.10 Obstack Chunks

Obstacks work by allocating space for themselves in large chunks, and then parceling out space in the chunks to satisfy your requests. Chunks are normally 4096 bytes long unless you specify a different chunk size. The chunk size includes 8 bytes of overhead that are not actually used for storing objects. Regardless of the specified size, longer chunks will be allocated when necessary for long objects.

The obstack library allocates chunks by calling the function obstack_chunk_alloc, which you must define. When a chunk is no longer needed because you have freed all the objects in it, the obstack library frees the chunk by calling obstack_chunk_free, which you must also define.

These two must be defined (as macros) or declared (as functions) in each source file that uses obstack_init (see Creating Obstacks). Most often they are defined as macros like this:

     #define obstack_chunk_alloc malloc
     #define obstack_chunk_free free

Note that these are simple macros (no arguments). Macro definitions with arguments will not work! It is necessary that obstack_chunk_alloc or obstack_chunk_free, alone, expand into a function name if it is not itself a function name.

If you allocate chunks with malloc, the chunk size should be a power of 2. The default chunk size, 4096, was chosen because it is long enough to satisfy many typical requests on the obstack yet short enough not to waste too much memory in the portion of the last chunk not yet used.

Since this macro expands to an lvalue, you can specify a new chunk size by assigning it a new value. Doing so does not affect the chunks already allocated, but will change the size of chunks allocated for that particular obstack in the future. It is unlikely to be useful to make the chunk size smaller, but making it larger might improve efficiency if you are allocating many objects whose size is comparable to the chunk size. Here is how to do so cleanly:

     if (obstack_chunk_size (obstack_ptr) < new-chunk-size)
       obstack_chunk_size (obstack_ptr) = new-chunk-size;

3.11 Summary of Obstack Functions

Here is a summary of all the functions associated with obstacks. Each takes the address of an obstack (struct obstack *) as its first argument.

void obstack_init (struct obstack *obstack-ptr)

Initialize use of an obstack. See Creating Obstacks.

void *obstack_alloc (struct obstack *obstack-ptr, int size)

Allocate an object of size uninitialized bytes. See Allocation in an Obstack.

void *obstack_copy (struct obstack *obstack-ptr, void *address, int size)

Allocate an object of size bytes, with contents copied from address. See Allocation in an Obstack.

void *obstack_copy0 (struct obstack *obstack-ptr, void *address, int size)

Allocate an object of size+1 bytes, with size of them copied from address, followed by a null character at the end. See Allocation in an Obstack.

void obstack_free (struct obstack *obstack-ptr, void *object)

Free object (and everything allocated in the specified obstack more recently than object). See Freeing Obstack Objects.

void obstack_blank (struct obstack *obstack-ptr, int size)

Add size uninitialized bytes to a growing object. See Growing Objects.

void obstack_grow (struct obstack *obstack-ptr, void *address, int size)

Add size bytes, copied from address, to a growing object. See Growing Objects.

void obstack_grow0 (struct obstack *obstack-ptr, void *address, int size)

Add size bytes, copied from address, to a growing object, and then add another byte containing a null character. See Growing Objects.

void obstack_1grow (struct obstack *obstack-ptr, char data-char)

Add one byte containing data-char to a growing object. See Growing Objects.

void *obstack_finish (struct obstack *obstack-ptr)

Finalize the object that is growing and return its permanent address. See Growing Objects.

int obstack_object_size (struct obstack *obstack-ptr)

Get the current size of the currently growing object. See Growing Objects.

void obstack_blank_fast (struct obstack *obstack-ptr, int size)

Add size uninitialized bytes to a growing object without checking that there is enough room. See Extra Fast Growing.

void obstack_1grow_fast (struct obstack *obstack-ptr, char data-char)

Add one byte containing data-char to a growing object without checking that there is enough room. See Extra Fast Growing.

int obstack_room (struct obstack *obstack-ptr)

Get the amount of room now available for growing the current object. See Extra Fast Growing.

int obstack_alignment_mask (struct obstack *obstack-ptr)

The mask used for aligning the beginning of an object. This is an lvalue. See Obstacks Data Alignment.

int obstack_chunk_size (struct obstack *obstack-ptr)

The size for allocating chunks. This is an lvalue. See Obstack Chunks.

void *obstack_base (struct obstack *obstack-ptr)

Tentative starting address of the currently growing object. See Status of an Obstack.

void *obstack_next_free (struct obstack *obstack-ptr)

Address just after the end of the currently growing object. See Status of an Obstack.

4 Function, Variable, and Macro Listing.

Appendix A Licenses

• Library Copying: The GNU Library General Public License
• BSD: Regents of the University of California

A.1 GNU LESSER GENERAL PUBLIC LICENSE

     Copyright © 1991, 1999 Free Software Foundation, Inc.
     51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA
     
     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.
     
     [This is the first released version of the Lesser GPL.  It also counts
     as the successor of the GNU Library Public License, version 2, hence the
     version number 2.1.]

A.1.1 Preamble

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A.1.2 How to Apply These Terms to Your New Libraries

If you develop a new library, and you want it to be of the greatest possible use to the public, we recommend making it free software that everyone can redistribute and change. You can do so by permitting redistribution under these terms (or, alternatively, under the terms of the ordinary General Public License).

To apply these terms, attach the following notices to the library. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the “copyright” line and a pointer to where the full notice is found.

     one line to give the library's name and an idea of what it does.
     Copyright (C) year  name of author
     
     This library is free software; you can redistribute it and/or modify it
     under the terms of the GNU Lesser General Public License as published by
     the Free Software Foundation; either version 2.1 of the License, or (at
     your option) any later version.
     
     This library is distributed in the hope that it will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Lesser General Public License for more details.
     
     You should have received a copy of the GNU Lesser General Public
     License along with this library; if not, write to the Free Software
     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
     USA.

Also add information on how to contact you by electronic and paper mail.

You should also get your employer (if you work as a programmer) or your school, if any, to sign a “copyright disclaimer” for the library, if necessary. Here is a sample; alter the names:

     Yoyodyne, Inc., hereby disclaims all copyright interest in the library
     `Frob' (a library for tweaking knobs) written by James Random Hacker.
     
     signature of Ty Coon, 1 April 1990
     Ty Coon, President of Vice

That's all there is to it!

A.2 BSD

Copyright © 1990 Regents of the University of California. All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
3. [rescinded 22 July 1999]
4. Neither the name of the University nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS “AS IS” AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Index

• alignment (in obstacks): Obstacks Data Alignment
• alloca: Functions
• allocation (obstacks): Allocation in an Obstack
• asprintf: Functions
• atexit: Functions
• basename: Functions
• bcmp: Functions
• bcopy: Functions
• bsearch: Functions
• buildargv: Functions
• bzero: Functions
• calloc: Functions
• changing the size of a block (obstacks): Growing Objects
• choose_temp_base: Functions
• choose_tmpdir: Functions
• chunks: Obstack Chunks
• clock: Functions
• concat: Functions
• dupargv: Functions
• efficiency and obstacks: Extra Fast Growing
• efficiency of chunks: Obstack Chunks
• errno_max: Functions
• error reporting: Error Reporting
• exit handlers: Exit Handlers
• expandargv: Functions
• extensions: Extensions
• fdmatch: Functions
• fdopen_unlocked: Functions
• ffs: Functions
• filename_cmp: Functions
• fnmatch: Functions
• fopen_unlocked: Functions
• freeargv: Functions
• freeing (obstacks): Freeing Obstack Objects
• freopen_unlocked: Functions
• functions, extension: Extensions
• functions, missing: Supplemental Functions
• functions, replacement: Replacement Functions
• functions, supplemental: Supplemental Functions
• get_run_time: Functions
• getcwd: Functions
• getpagesize: Functions
• getpwd: Functions
• gettimeofday: Functions
• growing objects (in obstacks): Growing Objects
• hex_init: Functions
• hex_p: Functions
• hex_value: Functions
• HOST_CHARSET: Functions
• HOST_CHARSET_ASCII: Functions
• HOST_CHARSET_EBCDIC: Functions
• HOST_CHARSET_UNKNOWN: Functions
• how to use: Using
• index: Functions
• initstate: Functions
• insque: Functions
• IS_ISOBASIC: Functions
• IS_NVSPACE: Functions
• IS_SPACE_OR_NUL: Functions
• IS_VSPACE: Functions
• ISALNUM: Functions
• ISALPHA: Functions
• ISBLANK: Functions
• ISCNTRL: Functions
• ISDIGIT: Functions
• ISGRAPH: Functions
• ISIDNUM: Functions
• ISIDST: Functions
• ISLOWER: Functions
• ISPRINT: Functions
• ISPUNCT: Functions
• ISSPACE: Functions
• ISUPPER: Functions
• ISXDIGIT: Functions
• lbasename: Functions
• LGPL, Lesser General Public License: Library Copying
• libiberty usage: Using
• lrealpath: Functions
• macros: Obstack Functions
• make_relative_prefix: Functions
• make_temp_file: Functions
• memchr: Functions
• memcmp: Functions
• memcpy: Functions
• memmove: Functions
• memory allocation: Memory Allocation
• mempcpy: Functions
• memset: Functions
• mkstemps: Functions
• obstack status: Status of an Obstack
• obstack.h: Creating Obstacks
• obstack_1grow: Growing Objects
• obstack_1grow_fast: Extra Fast Growing
• obstack_alignment_mask: Obstacks Data Alignment
• obstack_alloc: Allocation in an Obstack
• obstack_alloc_failed_handler: Preparing for Obstacks
• obstack_base: Status of an Obstack
• obstack_blank: Growing Objects
• obstack_blank_fast: Extra Fast Growing
• obstack_chunk_alloc: Preparing for Obstacks
• obstack_chunk_free: Preparing for Obstacks
• obstack_chunk_size: Obstack Chunks
• obstack_copy: Allocation in an Obstack
• obstack_copy0: Allocation in an Obstack
• obstack_finish: Growing Objects
• obstack_free: Freeing Obstack Objects
• obstack_grow: Growing Objects
• obstack_grow0: Growing Objects
• obstack_init: Preparing for Obstacks
• obstack_int_grow: Growing Objects
• obstack_int_grow_fast: Extra Fast Growing
• obstack_next_free: Status of an Obstack
• obstack_object_size: Status of an Obstack
• obstack_object_size: Growing Objects
• obstack_ptr_grow: Growing Objects
• obstack_ptr_grow_fast: Extra Fast Growing
• obstack_room: Extra Fast Growing
• obstacks: Obstacks
• PEX_BINARY_ERROR: Functions
• PEX_BINARY_INPUT: Functions
• PEX_BINARY_OUTPUT: Functions
• pex_free: Functions
• pex_get_status: Functions
• pex_get_times: Functions
• pex_init: Functions
• pex_input_file: Functions
• pex_input_pipe: Functions
• PEX_LAST: Functions
• pex_one: Functions
• pex_read_err: Functions
• pex_read_output: Functions
• PEX_RECORD_TIMES: Functions
• pex_run: Functions
• pex_run_in_environment: Functions
• PEX_SAVE_TEMPS: Functions
• PEX_SEARCH: Functions
• PEX_STDERR_TO_PIPE: Functions
• PEX_STDERR_TO_STDOUT: Functions
• PEX_SUFFIX: Functions
• PEX_USE_PIPES: Functions
• pexecute: Functions
• psignal: Functions
• putenv: Functions
• pwait: Functions
• random: Functions
• reconcat: Functions
• remque: Functions
• rename: Functions
• replacement functions: Replacement Functions
• rindex: Functions
• setenv: Functions
• setstate: Functions
• shrinking objects: Growing Objects
• signo_max: Functions
• sigsetmask: Functions
• snprintf: Functions
• spaces: Functions
• srandom: Functions
• status of obstack: Status of an Obstack
• stpcpy: Functions
• stpncpy: Functions
• strcasecmp: Functions
• strchr: Functions
• strdup: Functions
• strerrno: Functions
• strerror: Functions
• strncasecmp: Functions
• strncmp: Functions
• strndup: Functions
• strrchr: Functions
• strsignal: Functions
• strsigno: Functions
• strstr: Functions
• strtod: Functions
• strtoerrno: Functions
• strtol: Functions
• strtosigno: Functions
• strtoul: Functions
• strverscmp: Functions
• supplemental functions: Supplemental Functions
• tmpnam: Functions
• unlink_if_ordinary: Functions
• unlock_std_streams: Functions
• unlock_stream: Functions
• unsetenv: Functions
• using libiberty: Using
• vasprintf: Functions
• vfork: Functions
• vfprintf: Functions
• vprintf: Functions
• vsnprintf: Functions
• vsprintf: Functions
• waitpid: Functions
• writeargv: Functions
• xatexit: Functions
• xcalloc: Functions
• xexit: Functions
• xmalloc: Functions
• xmalloc_failed: Functions
• xmalloc_set_program_name: Functions
• xmemdup: Functions
• xrealloc: Functions
• xstrdup: Functions
• xstrerror: Functions
• xstrndup: Functions