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array_truncate(3) [debian man page]

array_truncate(3)					     Library Functions Manual						 array_truncate(3)

NAME
array_truncate - reduce number of initialized bytes SYNTAX
#include <array.h> void array_truncate(array* x, uint64 membersize, int64 len); array_truncate(&x,sizeof(t),len); DESCRIPTION
array_truncate reduces the number of initialized bytes in x to exactly len*sizeof(t). If the number of initialized bytes was already this small (or smaller), array_truncate has no effect. If len is negative, array_truncate has no effect. If x is unallocated, array_truncate has no effect. If x has failed, array_truncate has no effect. array_truncate does not change the allocation in x. If you want to free the memory used by x, use array_reset. SEE ALSO
array_allocate(3), array_get(3), array_fail(3), array_trunc(3), array_reset(3) array_truncate(3)

Check Out this Related Man Page

stralloc(3)						     Library Functions Manual						       stralloc(3)

NAME
stralloc - dynamically allocated strings SYNTAX
#include <stralloc.h> int stralloc_ready(&sa,len); int stralloc_readyplus(&sa,len); int stralloc_copy(&sa,&sa2); int stralloc_copys(&sa,buf); int stralloc_copyb(&sa,buf,len); int stralloc_cat(&sa,&sa2); int stralloc_cats(&sa,buf); int stralloc_catb(&sa,buf,len); int stralloc_append(&sa,buf); int stralloc_0(&sa); int stralloc_starts(&sa,buf); stralloc sa = {0}; stralloc sa2 = {0}; unsigned int len; char *buf; DESCRIPTION
A stralloc variable holds a string in dynamically allocated space. String length is limited only by memory. String contents are unre- stricted. The stralloc structure has three components: sa.s is a pointer to the string, or 0 if it is not allocated; sa.len is the number of bytes in the string, if it is allocated; sa.a is the number of bytes allocated for the string, if it is allocated. A stralloc variable should be initialized to {0}, meaning unallocated. stralloc_ready makes sure that sa has enough space allocated for len characters. It allocates extra space if necessary. stralloc_readyplus makes sure that sa has enough space allocated for len characters more than its current length. If sa is unallocated, stralloc_readyplus is the same as stralloc_ready. stralloc_copy copies sa2 to sa, allocating space if necessary. Here sa2 is an allocated stralloc variable. stralloc_copys copies a 0-terminated string, buf, to sa, without the 0. stralloc_copyb copies len characters from buf to sa. stralloc_cat appends sa2 to sa, allocating space if necessary. If sa is unallocated, stralloc_cat is the same as stralloc_copy. stralloc_cats and stralloc_catb are analogous to stralloc_copys and stralloc_copyb. stralloc_append adds a single character, *buf, to sa, allocating space if necessary. stralloc_0 adds a single 0 character to sa. stralloc_starts returns 1 if the 0-terminated string buf, without the 0, is a prefix of sa. ERROR HANDLING
If a stralloc routine runs out of memory, it leaves sa alone and returns 0, setting errno appropriately. On success it returns 1; this guarantees that sa is allocated. SEE ALSO
alloc(3), error(3) stralloc(3)
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