47 lines
1.0 KiB
C
47 lines
1.0 KiB
C
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/*
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Copyright (C) 2016-2019 The University of Notre Dame
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This software is distributed under the GNU General Public License.
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See the file LICENSE for details.
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*/
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/*
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A trivial user level program to try out basic system calls.
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*/
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#include "library/syscalls.h"
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#include "library/string.h"
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#include "library/user-io.h"
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int main(int argc, char *argv[])
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{
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syscall_chdir("/");
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printf("got root\n");
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int fd = syscall_open_file("kevin", 2, 0);
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printf("got fd %d\n", fd);
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printf("writing to file...\n");
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for(int i = 0; i < 12; i++) {
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char buffer[4096] = {'a'+i};
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int n;
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n = syscall_object_write(fd, buffer, strlen(buffer));
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if(n < 0)
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break;
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printf("wrote %d chars: %s\n", n, buffer);
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}
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syscall_object_close(fd);
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fd = syscall_open_file("kevin", 1, 0);
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printf("reading file...\n");
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for (int i = 0; i < 12; i++) {
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char buffer[4096];
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int n;
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while((n = syscall_object_read(fd, buffer, 4096-1)) > 0) {
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buffer[n] = 0;
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printf("%s");
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flush();
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}
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}
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syscall_object_close(fd);
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syscall_process_exit(0);
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return 0;
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}
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