malloc() Post: 302230010

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1 . Thanks everyone who read the post. 2 . the programe is that : #include <stdio.h> #include <string.h> void do_it(char *p) { p = (char *) malloc(100); (void )strcpy(p,"1234"); } int main(void) { char *p; do_it(p); (void )printf("p = %s \n",p);

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hello sir since by mentioning a integer pointer and storing the integers by incrementing the pointer value then what is the purpose of malloc? u can decalre it as in t *p; several integers can be stored by incrementing the value of p, hence what is the diffrence between this...

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Hi! I hope this is the correct forum to post the question even if I'm a newbie... I am a C-newbie (and really on the edge to be a C-addict ;) ) and have a question. When should I use malloc? To state it differently, when should I NOT use malloc? For instance, if I have an array of...

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Do kmalloc and malloc allocate from same heap ?

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Hi i found code in google how to malloc an 2D array and i tried that : #include<stdio.h> #include<stdlib.h> int **A; int **B; int main(int argc,char *argv) { printf("name of text : %s\n",argv); //read arrays int i,j; int l,m; int M,n; FILE *fp; fp=fopen(argv,"r"); ...

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Good day! I'm a newbie in C. I'm trying to get an unlimited input from the user using malloc then printing the inputs after the user presses enter. My code works, but there's a warning that I don't know how to fix. Please help me. Thank you. Here's my code: #include <stdio.h> #include...

LEARN ABOUT MINIX

chmem

CHMEM(1)						      General Commands Manual							  CHMEM(1)

NAME

       chmem - change memory allocation

SYNOPSIS

       chmem [+] [-] [=] amount file

EXAMPLES

       chmem =50000 a.out  # Give a.out 50K of stack space

       chmem -4000 a.out   # Reduce the stack space by 4000 bytes

       chmem +1000 file1   # Increase each stack by 1000 bytes

DESCRIPTION

       When  a	program is loaded into memory, it is allocated enough memory for the text and data+bss segments, plus an area for the stack.  Data
       segment growth using malloc , brk , or sbrk eats up stack space from the low end.  The amount of stack space to allocate is derived from  a
       field  in  the executable program's file header.  If the combined stack and data segment growth exceeds the stack space allocated, the pro-
       gram will be terminated.

       It is therefore important to set the amount of stack space carefully.  If too little is provided, the program may crash.  If  too  much	is
       provided,  memory  will	be  wasted, and fewer programs will be able to fit in memory and run simultaneously.  MINIX does not swap, so that
       when memory is full, subsequent attempts to fork will fail.  The compiler sets the stack space to the largest possible value (for the Intel
       CPUs, 64K - text - data).  For many programs, this value is far too large.  Nonrecursive programs that do not call brk , sbrk , or malloc ,
       and do not have any local arrays usually do not need more than 8K of stack space.

       The chmem command changes the value of the header field that determines the stack allocation, and thus indirectly the total memory required
       to run the program.  The = option sets the stack size to a specific value; the + and - options increment and decrement the current value by
       the indicated amount.  The old and new stack sizes are printed.

SEE ALSO

       install(1), brk(2).

																	  CHMEM(1)

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