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XMALLOC(3pub)						       C Programmer's Manual						     XMALLOC(3pub)

NAME

       xmalloc, xrealloc, xfree, xstrdup, xmemdup, memdup - memory allocation functions for Publib

SYNOPSIS

       #include <publib.h>

       void *xmalloc(size_t bytes);
       void *xrealloc(void *ptr, size_t bytes);
       void xfree(void *ptr);
       char *xstrdup(const char *string);
       void *memdup(const void *mem, size_t bytes);
       void *xmemdup(const void *mem, size_t bytes);

DESCRIPTION

       These  functions are utility functions for memory allocation from the publib library.  xmalloc, xrealloc, and xfree are error checking ver-
       sions of the standard library routines malloc, realloc, and free, respectively.	They are guaranteed to never return unless  there  was	no
       problem:  if, for example, xmalloc is unable to allocate the requested amount of memory, it prints an error message and terminates the pro-
       gram.  Hence, the caller does not need to check for a NULL return value, and the code that calls these functions is simpler due to the lack
       of error checks.

       Similarly,  xstrdup  is an error checking version of the common (though not standard) strdup routine, which creates a duplicate of a string
       by allocating memory for the copy with malloc.  (For systems that lack strdup, publib provides one in its portability module; it is  always
       declared in <publib.h>.)

       memdup  is  similar to strdup, it creates a copy of an arbitrary memory area (the arguments are a pointer to the beginning of the area, and
       its size) by allocating memory for the copy with malloc.  xmemdup is its error checking version.

NOTE

       xmalloc and xrealloc treat a request to allocate a block of 0 bytes as an error.  xrealloc will allow its first argument to be NULL.

SEE ALSO

       publib(3), malloc(3), strdup(3)

AUTHOR

       Lars Wirzenius (lars.wirzenius@helsinki.fi)

Publib							       C Programmer's Manual						     XMALLOC(3pub)