There is no way to execute a compiled executable within a shell. Shells execute shell scripts, not binaries. If you need a side effect of a child process on the parent shell, your compiled program could output shell commands, which are intercepted and executed by the parent shell (sort of eval :-) )
For example, if the compiled program prints the following output to stdout:
Code:
ABC=123;
DEF=456;
cd /tmp;
and the shell starts the program like
Code:
eval $(./a.out)
the shell will define the two variables ABC and DEF and change the current working directory to /tmp.
Last edited by hergp; 04-09-2013 at 04:55 AM..
Reason: semicolons added
hi,
I am new ot unix. So, can i write a shell(c shell or korn shell) program to access internet? I mean if I run the program, it can access specified url and then copy the html to a file? Can anyone help me? And how can make the program runs every 1 hr?
new comer (2 Replies)
How do i run a shell script or perl script with in the context of a current shell.
I know that i can use command source. but we can't pass any arguments to
our script if we use source command as it takes only one argement i.e filename
Is there any way to run a script in the current shell... (5 Replies)
Hi,
i want to write a script that executes a program (exec?) .
this program then requires a filename as input.
how do i give it this input in the script so the program will be complete run and close by the script.
e.g.
exec prog.exe
program then asks for filename
"enter filename:"... (1 Reply)
How does the program know the full path of itself when the program is running in certain diretory? BTW, I have no "argv" information of main() functino.
(The program is written in C++ on linux platform) (1 Reply)
I have a file as follows:
cat /etc/mxg/ssh-hostsmx.example1.com.au:2225
mx2.example2.com.au:2225
mx.example3.com.au:2225
mail.example4.com.au:2225
mail.example5.org.au:2225
mail.example6.com.au:2225I want to dynamically create aliases for quick access to these servers from bash. I wrote... (4 Replies)
Hi
I want to create a shell script tha executes a C program and then retrieves information about it.
I managed to run the program with:
#!/bin/bash
gcc -o program program.c
./program
Now i want to get the id of the process (pid)
Any help would be appreciated,
Thank you (18 Replies)
I want to add a crontab entry which should execute for every 4 hours and that 4 hours calculation should begin from the current time.
Normally if I set the crontab entry like this,
00 */4 30 05 * root date >>/tmp/cronout
The above will execute the date command for every 4 hours like... (7 Replies)
Hi All,
well , i am facing this problem.. i have tried a few sample codes but there isn't any solution . could anyone please give a sample code as of how to do this...
Please see the below details...and read the details carefully.
I have written some code, logic is
1)from... (4 Replies)
Discussion started by: aish11
4 Replies
LEARN ABOUT OSF1
source
exec(1) User Commands exec(1)NAME
exec, eval, source - shell built-in functions to execute other commands
SYNOPSIS
sh
exec [argument...]
eval [argument...]
csh
exec command
eval argument...
source [-h] name
ksh
*exec [arg...]
*eval [arg...]
DESCRIPTION
sh
The exec command specified by the arguments is executed in place of this shell without creating a new process. Input/output arguments may
appear and, if no other arguments are given, cause the shell input/output to be modified.
The arguments to the eval built-in are read as input to the shell and the resulting command(s) executed.
csh
exec executes command in place of the current shell, which terminates.
eval reads its arguments as input to the shell and executes the resulting command(s). This is usually used to execute commands generated as
the result of command or variable substitution.
source reads commands from name. source commands may be nested, but if they are nested too deeply the shell may run out of file descrip-
tors. An error in a sourced file at any level terminates all nested source commands.
-h Place commands from the file name on the history list without executing them.
ksh
With the exec built-in, if arg is given, the command specified by the arguments is executed in place of this shell without creating a new
process. Input/output arguments may appear and affect the current process. If no arguments are given the effect of this command is to mod-
ify file descriptors as prescribed by the input/output redirection list. In this case, any file descriptor numbers greater than 2 that are
opened with this mechanism are closed when invoking another program.
The arguments to eval are read as input to the shell and the resulting command(s) executed.
On this man page, ksh(1) commands that are preceded by one or two * (asterisks) are treated specially in the following ways:
1. Variable assignment lists preceding the command remain in effect when the command completes.
2. I/O redirections are processed after variable assignments.
3. Errors cause a script that contains them to abort.
4. Words, following a command preceded by ** that are in the format of a variable assignment, are expanded with the same rules as a vari-
able assignment. This means that tilde substitution is performed after the = sign and word splitting and file name generation are not
performed.
EXIT STATUS
For ksh:
If command is not found, the exit status is 127. If command is found, but is not an executable utility, the exit status is 126. If a redi-
rection error occurs, the shell exits with a value in the range 1-125. Otherwise, exec returns a zero exit status.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO csh(1), ksh(1), sh(1), attributes(5)SunOS 5.10 17 Jul 2002 exec(1)
04-09-2013
