07-19-2008
Also, show what commands you use to measure free memory and swap and their output.
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1. UNIX for Dummies Questions & Answers
Hi All,:)
In my application malloc is returning NULL even though there is sufficient amount of free memory available but the swap memory is low.
Is this possible that, if free memory is high & swap memory is low, malloc will not be able to allocate memory & return NULL ?
Few details:
... (4 Replies)
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on the file Ftp'd from the mainframe ,do we have any UNIX command to replace mainframe low and values to space or null.
i tried using tr and it doesn't work ...
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Is it possible to have a bash script pick the highest and lowest values of four variables? I've been googling for this but haven't come up with anything. I have a script that assigns variables ($c0, $c1, $c2, and $c3) based on the coretemps from grep/sed statements of sensors. I'd like to also... (5 Replies)
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Hi guys,
i have a question about spliting a binary file into 2 chunks.
First chunk with all high bytes and the second one with all low bytes.
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Need some clarification on this....
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or
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6. UNIX for Advanced & Expert Users
OS : Solaris 10
When I try to get the "echo" service port, getservbyname is returning null.
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I have a system running AIX 61 shared uncapped partition (with 11 physical processors, 24 Virtual 72GB of Memory) .
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Hi team
I have three physical servers running on Red Hat Enterprise Linux Server release 6.2 with the following memory conditions:
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MemTotal: 8062888 kB
MemFree: 184540 kB
Shmem: 516 kB
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Hi All,
I am using malloc function for allocating dynamic memory.
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Hi all,
i have a binary file splitted into 2 chunks, first part with all high bytes and the second part with all low bytes.
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LEARN ABOUT XFREE86
bsdmalloc
bsdmalloc(3MALLOC) bsdmalloc(3MALLOC)
NAME
bsdmalloc - memory allocator
SYNOPSIS
cc [ flag ... ] file ... -lbsdmalloc [ library ... ]
char *malloc(size);
unsigned size;
int free( ptr);
char *ptr;
char *realloc( ptr, size);
char *ptr;
unsigned size;
These routines provide a general-purpose memory allocation package. They maintain a table of free blocks for efficient allocation and coa-
lescing of free storage. When there is no suitable space already free, the allocation routines call sbrk(2) to get more memory from the
system. Each of the allocation routines returns a pointer to space suitably aligned for storage of any type of object. Each returns a
null pointer if the request cannot be completed.
The malloc() function returns a pointer to a block of at least size bytes, which is appropriately aligned.
The free() function releases a previously allocated block. Its argument is a pointer to a block previously allocated by malloc() or real-
loc(). The free() function does not set errno.
The realloc() function changes the size of the block pointed to by ptr to size bytes and returns a pointer to the (possibly moved) block.
The contents will be unchanged up to the lesser of the new and old sizes. If the new size of the block requires movement of the block, the
space for the previous instantiation of the block is freed. If the new size is larger, the contents of the newly allocated portion of the
block are unspecified. If ptr is NULL, realloc() behaves like malloc() for the specified size. If size is 0 and ptr is not a null pointer,
the space pointed to is freed.
The malloc() and realloc() functions return a null pointer if there is not enough available memory. They return a non-null pointer if size
is 0. These pointers should not be dereferenced. When realloc() returns NULL, the block pointed to by ptr is left intact. Always cast the
value returned by malloc() and realloc().
If malloc() or realloc() returns unsuccessfully, errno will be set to indicate the following:
ENOMEM size bytes of memory cannot be allocated because it exceeds the physical limits of the system.
EAGAIN There is not enough memory available at this point in time to allocate size bytes of memory; but the application could try
again later.
Using realloc() with a block freed before the most recent call to malloc() or realloc() results in an error.
Comparative features of the various allocation libraries can be found in the umem_alloc(3MALLOC) manual page.
brk(2), malloc(3C), malloc(3MALLOC), mapmalloc(3MALLOC), umem_alloc(3MALLOC)
WARNINGS
Use of libbsdmalloc renders an application non-SCD compliant.
The libbsdmalloc routines are incompatible with the memory allocation routines in the standard C-library (libc): malloc(3C), alloca(3C),
calloc(3C), free(3C), memalign(3C), realloc(3C), and valloc(3C).
21 Mar 2005 bsdmalloc(3MALLOC)