I am writing a program that concatenates a line input from standard-input with a seperate file, and writes the combined text to an output file. For some reason when I type a full line of text into standard input, only the first word before whitespace is being written. What's wrong with my code?
Accepting from std-in and writing:
// check for stdinput flag
if(strcmp(argv[1], "-") == 0) // use standard-in for input file 1
{
printf("Type your text and then hit enter: ");
p = fgets(userInput, sizeof(userInput), stdin);
if (write(output_file, userInput, sizeof(p)) < 0) // write stdin to output file
{
perror(argv[4]);
close(output_file);
exit(1);
}
}
Further along in the program... writing the second file to output:
else // open file2 and assign to file-handler, then output to file
{
if((input_file2 = open(argv[2], O_RDONLY)) < 0)
{
perror(argv[2]);
close(output_file); // close the opened output file handler
exit(1);
}
while((n = read(input_file2, buffer, sizeof(buffer))) > 0)
{
if((write(output_file, buffer, n)) < 0)
{
perror(argv[3]);
close(input_file2);
close(output_file);
exit(1);
}
}
close(input_file2);
}
command line and output:
server1{user25}35: program - file2 outputfile
Type your text and then hit enter: THIS IS MY TEXT FROM STDIN
server1{user25}36: cat outputfile
THISthis is the text in file2
server1{user25}37:
In your first fragment, you output sizeof(p)
characters which is sizeof(char*)
(which on a 64-bit system would be 8 bytes). You need to change this to at least strlen(p)
(obviously, after checking for an error and NULL
return value).