38 lines
1.1 KiB
C
38 lines
1.1 KiB
C
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// Writes data to a file which is readable and writable by the user by
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// specificying permissions
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <errno.h>
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#include <sys/stat.h>
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#include <fcntl.h>
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#define BUFSIZE 128
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int main(int argc, char *argv[]){
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char *outfile = "readable.txt";
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printf("Opening file %s\n",outfile);
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mode_t mode = S_IRUSR | S_IWUSR;
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int out_fd = open(outfile,O_WRONLY | O_CREAT, mode); // open for writing and create if needed, WITH PERMISSIONS
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if(out_fd == -1){ // check result and fail if not opened
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perror("Couldn't open output file");
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exit(1);
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}
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printf("Writing to file %s\n",outfile);
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char outbuf[BUFSIZE] = "here is some text to write"; // what to write
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int bytes_written = write(out_fd, outbuf, BUFSIZE); // do th write
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if(bytes_written == -1){ // check for errors
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perror("Failed to read from file");
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exit(1);
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}
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printf("Wrote %d bytes to %s\n",bytes_written,outfile);
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if(close(out_fd) == -1){ // check for errors on close
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perror("Couldn't close file");
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}
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return 0;
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}
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