Enrico Fraccaroli (Galfurian)
70 lines
1.8 KiB
C
70 lines
1.8 KiB
C
/// @file man.c
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/// @brief Shows the available commands.
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/// @copyright (c) 2014-2022 This file is distributed under the MIT License.
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/// See LICENSE.md for details.
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#include <fcntl.h>
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#include <stdio.h>
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#include <strerror.h>
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#include <string.h>
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#include <sys/dirent.h>
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#include <sys/unistd.h>
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int main(int argc, char *argv[])
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{
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if (argc == 1)
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{
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int fd = open("/bin", O_RDONLY | O_DIRECTORY, 0);
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if (fd == -1)
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{
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printf("%s: cannot access '/bin': %s\n\n", argv[0], strerror(errno));
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return 1;
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}
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dirent_t dent;
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int per_line = 0;
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while (getdents(fd, &dent, sizeof(dirent_t)) == sizeof(dirent_t))
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{
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// Shows only regular files
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if (dent.d_type == DT_REG)
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{
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printf("%10s ", dent.d_name);
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if (++per_line == 6)
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{
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per_line = 0;
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putchar('\n');
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}
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}
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}
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putchar('\n');
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close(fd);
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}
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else if (argc == 2)
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{
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char filepath[PATH_MAX];
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strcpy(filepath, "/usr/share/man/");
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strcat(filepath, argv[1]);
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strcat(filepath, ".man");
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int fd = open(filepath, O_RDONLY, 42);
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if (fd < 0)
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{
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printf("%s: No manual entry for %s\n\n", argv[0], argv[1]);
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}
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else
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{
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// Prepare the buffer for reading the man file.
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char buffer[BUFSIZ];
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// Put on the standard output the characters.
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while (read(fd, buffer, BUFSIZ) > 0)
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{
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puts(buffer);
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}
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// Close the file descriptor.
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close(fd);
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// Terminate with a pair of newlines.
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putchar('\n');
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putchar('\n');
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}
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}
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return 0;
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}
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