Hi,
I have an issue where i run an command in a shell script.
If the command returns an error i'm redirecting it to /dev/null.
The prob is if an error comes it expects the user to press return to continue.
And hence the return is not echoed. and the end user is not aware of this.
Please help me provide an automatic input incase of error.
Cant use expect and spawn due to certain limitations.
Please help.
Last edited by Scrutinizer; 04-27-2012 at 04:55 PM..
Reason: code tags
hi all..
I am running this command in linux from a shell script....gpg --output encrypted_file.gpg --encrypt --recipient santhosh@yahoo.com /home/test2/actectest/san.zip.....this is a command for encrypting a file using GnuPG tool.....and while the command is running it stops in between... (1 Reply)
Hi,
In a shell script i am running a command which is asking for input.
How can i give that automatically.
I have done this before but for the time being can't recall.
Was something like <|
Thanks (6 Replies)
Hi,
I am triying to make sure that there exists only one file with the pattern abc* in path /path/. This directory is having many huge files. If there is only one file then I have to take its complete name only to use furter in my script.
I am planning to do like this:
if ; then... (2 Replies)
I'm trying to send a command automatically via Telnet, but without success.
I can do this:
> telnet 100.100.100.1 8080
Trying 100.100.100.1...
Connected to 100.100.100.1.
Escape character is '^]'.
Whereby I enter "command" and everything works like a charm, but I'd like to do this... (3 Replies)
i have got many files like this in my folder temp(say)
imp_02042008.txt for date 02-04-2008
imp_03092009.txt for date 03-09-2009
imp_25112009.txt for date 25-11-2009
...................
........
in some folder.
and one of my shell code uses one of the above files based on date.... (0 Replies)
i have got many files like this in my folder temp(say)
imp_02042008.txt for date 02-04-2008
imp_03092009.txt for date 03-09-2009
imp_25112009.txt for date 25-11-2009
...................
........
in some folder.
and one of my shell code uses one of the above files based on date.... (9 Replies)
Output file template format
<input_file_name>a</input_file_name>
<total_length_size>b</total_length_size>
<log_10_length_size>c</log_10_length_size>
Input_file_1 (eg. sample.txt)
SDFSDGDGSFGRTREREYWW
Parameter:
a is equal to the input file name
b is equal to the total length of... (2 Replies)
Hi,
Please help me,its urgent.
I have a tool that i want to run from a shell script. When we run the tool it will ask the user choice to add or delete. When user enter the choice it will then ask how many units he want to delete or add and will add or delete accordingly.
Now I want to... (1 Reply)
Hello there, I am posting to seek help with a KSH script,
I am making a simple calculation program where the user can enter as many numbers as they like, I am getting their input using the read command, however I am not sure how to repeat doing this and storing the input in to new variables... (7 Replies)
Hi All,
I need a favour.
I have a file called "redhat_servers.txt" containing some server names line by line.
When I try to ssh to each server, and I have already done with ssh key-gen stuff. Now, for first time if I do ssh .. I need to type yes I have more than 400 servers...it will take... (4 Replies)
Discussion started by: kumar85shiv
4 Replies
LEARN ABOUT CENTOS
system
SYSTEM(3) Linux Programmer's Manual SYSTEM(3)NAME
system - execute a shell command
SYNOPSIS
#include <stdlib.h>
int system(const char *command);
DESCRIPTION
system() executes a command specified in command by calling /bin/sh -c command, and returns after the command has been completed. During
execution of the command, SIGCHLD will be blocked, and SIGINT and SIGQUIT will be ignored.
RETURN VALUE
The value returned is -1 on error (e.g., fork(2) failed), and the return status of the command otherwise. This latter return status is in
the format specified in wait(2). Thus, the exit code of the command will be WEXITSTATUS(status). In case /bin/sh could not be executed,
the exit status will be that of a command that does exit(127).
If the value of command is NULL, system() returns nonzero if the shell is available, and zero if not.
system() does not affect the wait status of any other children.
CONFORMING TO
C89, C99, POSIX.1-2001.
NOTES
If the _XOPEN_SOURCE feature test macro is defined (before including any header files), then the macros described in wait(2) (WEXITSTA-
TUS(), etc.) are made available when including <stdlib.h>.
As mentioned, system() ignores SIGINT and SIGQUIT. This may make programs that call it from a loop uninterruptible, unless they take care
themselves to check the exit status of the child. E.g.
while (something) {
int ret = system("foo");
if (WIFSIGNALED(ret) &&
(WTERMSIG(ret) == SIGINT || WTERMSIG(ret) == SIGQUIT))
break;
}
Do not use system() from a program with set-user-ID or set-group-ID privileges, because strange values for some environment variables might
be used to subvert system integrity. Use the exec(3) family of functions instead, but not execlp(3) or execvp(3). system() will not, in
fact, work properly from programs with set-user-ID or set-group-ID privileges on systems on which /bin/sh is bash version 2, since bash 2
drops privileges on startup. (Debian uses a modified bash which does not do this when invoked as sh.)
In versions of glibc before 2.1.3, the check for the availability of /bin/sh was not actually performed if command was NULL; instead it was
always assumed to be available, and system() always returned 1 in this case. Since glibc 2.1.3, this check is performed because, even
though POSIX.1-2001 requires a conforming implementation to provide a shell, that shell may not be available or executable if the calling
program has previously called chroot(2) (which is not specified by POSIX.1-2001).
It is possible for the shell command to return 127, so that code is not a sure indication that the execve(2) call failed.
SEE ALSO sh(1), signal(2), wait(2), exec(3)COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
2010-09-10 SYSTEM(3)