57 lines
1.3 KiB
C
57 lines
1.3 KiB
C
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/* This file is part of the sample code and exercises
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* used by the class "Advanced Programming in the UNIX
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* Environment" taught by Jan Schaumann
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* <jschauma@netmeister.org> at Stevens Institute of
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* Technology.
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*
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* This file is in the public domain.
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*
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* You don't have to, but if you feel like
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* acknowledging where you got this code, you may
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* reference me by name, email address, or point
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* people to the course website:
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* https://stevens.netmeister.org/631/
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*/
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/* This program is all sorts of terrible. If I catch
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* you doing anything like this in your code, you'll
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* have a hard time getting any points.
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*
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* We use this code to illustrate how "strings" work,
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* as well as how to inspect arrays and pointers using
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* gdb(1).
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*
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* Compile this with '-g'. Run it as './a.out foo',
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* then run it in the debugger, break in 'main', and
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* inspect the different pointers at each step to
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* better understand what is going on.
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*/
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#include <stdio.h>
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#include <string.h>
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int
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main(int argc, char **argv) {
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char *p = argv[0];
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char *q = argv[1];
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(void)argc;
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strcat(argv[0], "/");
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strcat(p, argv[1]);
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printf("argv[0]: %s\n", argv[0]);
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printf("argv[1]: %s\n\n", argv[1]);
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*(p + 1) = '\0';
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q[0] = 'm';
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printf("argv[0]: %s\n", argv[0]);
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printf("argv[0]: %s\n", argv[0]);
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p[1] = '/';
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printf("argv[0]: %s\n", argv[0]);
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return 0;
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}
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