No output file created when compiled with gcc - java

Calling gcc compiler in a Java Source to compile a C file.
List<String> command = new ArrayList<String>();
String fs = System.getProperty("file.separator");
command.add("C:\\cygwin" + fs + "bin" + fs + "sh");
command.add("-c");
command.add("/usr/bin/gcc /cygdrive/d/WorkSpace/TEST/HelloWorld.c -o /cygdrive/d/WorkSpace/HHH");
ProcessBuilder builder = new ProcessBuilder(command);
final Process process = builder.start();
HHH.exe is not created. Can somebody explain me what is wrong with this code?

You need to make the strings "cmd" and "/c" the first two elements in the command list. This is necessary when invoking any command line process from Java.

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Java switch directories and then fire command with parameters

Hey all I am trying to change directories and then run my command with parameters.
final String path = "\\Local// Apps\\IBM\\SDP\\scmtools\\eclipse";
final String command = "scm help";
final String dosCommand = "cmd /c \"" + path + "\"" + command;
final Process process = Runtime.getRuntime().exec(dosCommand);
final InputStream in = process.getInputStream();
int ch;
while((ch = in.read()) != -1) {
System.out.print((char)ch);
}
It runs without errors but outputs nothing. However, this is what shows up after it finishes:
<terminated, exit value: 0>C:\Local Apps\IBM\SDP\jdk\bin\javaw.exe (Jul 22, 2019, 11:21:37 AM)
The expected output should be:
So am I doing this correctly?
AS suggested by Andreas
Process p = null;
ProcessBuilder pb = new ProcessBuilder("scm.exe");
pb.directory(new File("C:/Local Apps/IBM/SDP/scmtools/eclipse"));
p = pb.start();
I get the following error:
Cannot run program "scm.exe" (in directory "C:\Local Apps\IBM\SDP\scmtools\eclipse"): CreateProcess error=2, The system cannot find the file specified
You should use ProcessBuilder instead of Runtime.exec, e.g.
Process proc = new ProcessBuilder("scm.exe", "help")
.directory(new File("C:\\Local Apps\\IBM\\SDP\\scmtools\\eclipse"))
.inheritIO()
.start();
proc.waitFor(); // optional
You can also go through the command interpreter if needed, e.g. if the command is a script (.bat or .cmd file):
Process proc = new ProcessBuilder("cmd", "/c", "scm", "help")
.directory(new File("C:\\Local Apps\\IBM\\SDP\\scmtools\\eclipse"))
.inheritIO()
.start();
proc.waitFor();
The inheritIO() means that you don't need to process the commands output. It will be sent to the console, or wherever Java's own output would go.

Run exec file using Java on Mac

I need to start a server using bash, so I had created an UNIX shell , but I am not able to execute it with Java from Eclipse.
I tried the following code which doesn't work :
Process proc = Runtime.getRuntime().exec(./startServer);
Here is content of the startServer file :
#!/bin/bash
cd /Users/sujitsoni/Documents/bet/client
npm start
You can try the following two options.
Option 1
Process proc = Runtime.getRuntime().exec("/bin/bash", "-c", "<Abosulte Path>/startServer");
Option 2
ProcessBuilder pb = new ProcessBuilder("/bin/bash", "-c", "<Absolute Path>/startServer");
pb.directory(new File("<Absolute Path>"));
Process proc = pb.start();
A couple Of things can go wrong:
The path to the file you have given might be wrong for eclipse it can take relative path but from the command line, it will take the absolute path.
error=13, Permission denied - If the script file doesn't have required permissions. In your scenario, that might not the case as you are not getting any error.
At last, you are executing the script by java program so the output of your script will not be printed out. In your scenario, this might be the case. You need to capture the output of script from BufferedReade and print it. ( In your case server might have started but you are not seeing the logs/output of the script.
See the code sample below for printing output.
public static void main(String[] args) throws IOException, InterruptedException {
Process proc = Runtime.getRuntime().exec("./startServer");
proc.waitFor();
StringBuffer output = new StringBuffer();
BufferedReader reader = new BufferedReader(new InputStreamReader(proc.getInputStream()));
String line = "";
while ((line = reader.readLine()) != null) {
output.append(line + "\n");
}
System.out.println(output);
}

"Program Files" command intern not found CMD

I use java to excute a command line to create a database, i get an error when i excute this piece of code:
private final String POSTGRES_PATH = "\"C:\\Program Files\\PostgreSQL\\9.3\\bin\\psql.exe\"";
private final String DATA_BASE = "bd_name";
private void creerDataBase() {
String command = this.POSTGRES_PATH + " -U postgres -d postgres -c \"CREATE DATABASE " + this.DATA_BASE + "\"";
System.out.println("command = " + command);
String creerBDD = executerCommande(command);
System.out.println("Resultat : " + creerBDD);
}
public String executerCommande(String command) {
String line;
String resultat = "";
try {
ProcessBuilder builder = new ProcessBuilder("cmd.exe", "/c", command);
builder.redirectErrorStream(true);
Process p = builder.start();
BufferedReader r = new BufferedReader(new InputStreamReader(p.getInputStream()));
while (true) {
line = r.readLine();
if (line == null) {
break;
}
resultat += line + "\n";
}
} catch (Exception e) {
System.out.println("Exception = " + e.getMessage());
}
return resultat;
}
I get this result:
command = "C:\Program Files PostgreSQL\9.3\bin\psql.exe"\ -U postgres -d postgres -c "CREATE DATABASE bd_name"
and this error:
'C:\Program' n'est pas reconnu en tant que commande interne
This mean that Program is not an intern command.
but when i excute this command in CMD it work fine?
Is there any way to Build this Path because the ProcessBuilder not recognize C:\Program Files
Thanks for #Aaron his idea helps me so i solved this problem using this:
private final String POSTGRES_PATH = "C:\\PROGRA~1\\PostgreSQL\\9.3\\bin\\psql.exe";
this C:\\PROGRA~1 inteed of this: C:\\Program Files
A possible solution would be to remove the path (with spaces) from your constant field and use the directory method:
Sets this process builder's working directory. Subprocesses subsequently started by this object's start() method will use this as their working directory. The argument may be null -- this means to use the working directory of the current Java process, usually the directory named by the system property user.dir, as the working directory of the child process.
Changing your code to:
private final String POSTGRES_DIR = "C:\\Program Files\\PostgreSQL\\9.3\\bin\\"
private final String POSTGRES_COMMAND = "psql.exe";
....
ProcessBuilder builder = new ProcessBuilder("cmd.exe", "/c", command).directory(new File(POSTGRES_DIR));
.....
Don't run cmd.exe if you want to run a separate binary program.
cmd.exe is for scripts like *.cmd or *.bat
With cmd.exe you have to pass your command as an argument of CMD, and you should manage all OS-specific pitfalls like long paths with whitespaces, quotes inside qoutes etc.
Instead, you had better run psql itself.
The ProcessBuilder takes a command and all the arguments as a list of separate strings. And ProcessBuilder is clever enough to do all the necessary magic with quotes and whitespaces by itself.
And take attention to the list of arguments - shells separate arguments by whitespaces, while psql might recognize the sequence of strings as a single argument.
We may assume that -U postgress is a single argument for psql, but for shell (cmd.exe in our case) these are two separate arguments - -U and postgress, so we should pass them to the ProcessBuilder separately
So the better way to run psql is to run it directly, something like that:
new ProcessBuilder("C:\\Program Files\\PostgreSQL\\9.3\\bin\\psql.exe",
"-U", "postgres",
"-d", "postgres",
"-c", "\"CREATE DATABASE " + this.DATA_BASE + "\"");
What you could try is instead of the space between program and files is %20 or \s.
So like:
command = "C:\\Program%20Files\\PostgreSQL\\9.3\\bin\\psql.exe"
or
command = "C:\\Program\sFiles\\PostgreSQL\\9.3\\bin\\psql.exe"
I hope one of them works for you, please let me know
EDIT: use double \ to get it to recognize the \

How to change directory in java

I want to unzip tgz files using 7zip utility in Windows OS. My 7zip.exe file is placed in D: drive. My unzip command is 7z e abc.tgz. This command is working through terminal but not through my java code.
Previously I tried
Runtime r=Runtime.getRuntime();
r.exec("cmd.exe d: ", null, new File("D:\\"));
Process p=r.exec("7z e abc.tgz"null,new File("D:\\"));
InputStream is=p.getInputStream();
BufferedReader br= new BufferedReader(new InputStreamReader(is));
String line=new String();
while ((line=br.readLine())!=null) System.out.println (line);
I even tried this
ProcessBuilder pb = new ProcessBuilder("cmd.exe","/c","start","cmd");
pb = pb.directory(new File("D:"));
pb.command("7z", "e", "abc.tgz");
pb.start();
Is there any different method for changing the directory through java?
You can use this snippet to change the working directory:
String[] command = unzip_your_file;
ProcessBuilder builder = new ProcessBuilder(command);
builder.directory(new File("directory_location"));

Can't run ProcessBuilder

I am struggling with ProcessBuilder folks! I want to run the utility 'nativetoascii' in. I can run it on the command line and also via Runtime.exec() with no problems.
My code is:
'
String command = "\"C:\\Program Files (x86)\\Java\\jdk1.6.0_32\\bin\\native2ascii\"";
String encoding = " -encoding ";
String utf8 = "UTF8 ";
String inputFile = "C:\\Users\\joe\\Desktop\\resources\\encoding\\orig.properties ";
String outputFile ="C:\\Users\\joe\\Desktop\\resources\\encoding\\convertedViaProcessBuilder.properties";
List<String> commandArgs = new ArrayList<String>();
commandArgs.add(command);
commandArgs.add(encoding);
commandArgs.add(utf8);
commandArgs.add(inputFile);
commandArgs.add(outputFile);
ProcessBuilder builder = new ProcessBuilder(commandArgs);
Process p = builder.start();
p.waitFor();
I have also written code to read the output from the process and it says:
Usage: native2ascii [-reverse] [-encoding encoding] [inputfile [outputfile]]
Clearly I'm doing something wrong with the command and its arguments. Can anyone tell me what I'm doing wrong? Thanks.
Your second argument is " -encoding " which it would be "-encoding" Spaces matter when you run a command. ;)

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