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Full Discussion: Segmentation fault when I pass a char pointer to a function in C.
Top Forums Programming Segmentation fault when I pass a char pointer to a function in C. Post 303016290 by dryden on Tuesday 24th of April 2018 02:25:18 AM
Old 04-24-2018
Quote:
Originally Posted by Corona688
It's implicitly a pointer, implemented as one internally, but the same way you're not allowed to change a string's contents, you're not allowed to change its value. Hardcoded.
Those... aren't really similar things. The array's address (the name) is only known at compile time, or debug info, but in the compiled code the 'name' is effaced and you're simply dealing with addresses hardcoded into the code.

Thus, there isn't really anything you can modify unless you were to write the code segment.

The string, I guess it could also be located in a code segment, but more likely is that they are actual data values in a read-only data segment.

As such, the array is not really a pointer, there is no variable anywhere holding its address. So, it's no different from not being able to change the address of some int value that you have defined.

When you do

Code:
char arr[20]; char *p = arr;

That's technically no different from

Code:
int i; int *q = &i;

But I find the biggest annoyance(?) of arrays and structs to be that you can only initialize them at declaration?
 

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LEARN ABOUT DEBIAN

reverse-depends

reverse-depends(1)					      General Commands Manual						reverse-depends(1)

NAME

       reverse-depends - List the reverse-dependencies (or build-dependencies) of a package

SYNOPSIS

       reverse-depends [options] package

DESCRIPTION

       List  reverse-dependencies  (or build-dependencies) of package.	If the package name is prefixed with src: then the reverse-dependencies of
       all the binary packages that the specified source package builds will be listed.

OPTIONS

       -r RELEASE, --release=RELEASE
	      Query dependencies in RELEASE.  Default: current development release.

       -R, --without-recommends
	      Only consider Depends relationships, not Recommends.

       -s, --with-suggests
	      Also consider Suggests relationships.

       -b, --build-depends
	      Query build dependencies.  Synonym for --arch=source.

       -a ARCH, --arch=ARCH
	      Query dependencies in ARCH.  Besides valid architecture names, the special values any and source may  be	used.	any  displays  all
	      reverse dependencies, the union across all architecture.	source displays build dependencies.  Default: any.

       -c COMPONENT, --component=COMPONENT
	      Only consider reverse-dependencies in COMPONENT. Can be specified multiple times.  Default: all components.

       -l, --list
	      Display a simple, machine-readable list.

       -u URL, --service-url=URL
	      Reverse Dependencies web-service URL.  Default: UbuntuWire's service at http://qa.ubuntuwire.org/rdepends/.

       -h, --help
	      Display a help message and exit

EXAMPLES

       All reverse dependencies of source package bash:

	      reverse-depends src:bash

AUTHORS

       reverse-depends and this manpage were written by Stefano Rivera <stefanor@ubuntu.com>.

       Both are released under the terms of the ISC License.

ubuntu-dev-tools						   November 2011						reverse-depends(1)
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