code that reads commands from the standard i/p and executes the commands
Hello all,
i've written a small piece of code that will read commands from standard input and executes the commands.
Its working fine and is execting the commands well. Accepting arguments too. e.g
#mkdir <name of the directory>
The problem is that its not letting me change the directory i.e pwd is remaining the same.
what changes should be made in it to let it change the directories too.
Can anyone tell me how/where to get the source code for the unix commands like "ls ,finger,cp....etc" commands . I
have tried very hard but failed so far.
Thanks
JAGDISH MACHHI (4 Replies)
I want to log into a remote server transfer over a new config and then backup the existing config, replace with the new config.
I am not sure if I can do this with BASH scripting.
I have set up password less login by adding my public key to authorized_keys file, it works.
I am a little... (1 Reply)
just curious -- I was wondering if it's possible to open the file for a command and look at the code (say for the command more). I've just read about the PATH variable and the type command to find out where the file is, but when I tried to open the file, the terminal exited and logged me out.
... (3 Replies)
Hi:
I have a requirement as below:
I have some standard Unix commands modified and kept them in a directory say /usr/clsh/bin. For example I have a script named "ls" kept here which is modified version of "ls" (say it always gives long listing i.e. ls -l).
When any user logs on and types... (2 Replies)
hi Folks!!
Just got a question in mind....
Is it possible for us to read the c code of the commands in the bin directory? I work on a LINUX server and i only see executables in the bin directory which i obviously can't read. Please help me regarding this.
Thanks in advance and wishing you a very... (2 Replies)
Hello All. I suspect that this will be a clear noob question, but I haven't been able to figure it out using the usual methods, so I turn to you.
I've written a script to create input files for the quantum chemistry program NWCHEM. Generally you create an input file and then execute it by... (12 Replies)
I need an if code in shell script where it should continue to further commands after succesfully installing the executable file.
i.e. /run installer is continuing but in the middle it executes further commands like "cp /root/user which were given after /run installer.
I want /runinstaller... (16 Replies)
Hi all,
I'm new in this forum.
I'm looking for the difference between the HACMP commands with the prefix "cl" and "cli".
The first type are under /usr/es/sbin/cluster/sbin directory and the second are under /usr/es/sbin/cluster/cspoc directory.
I know that the first are called HACMP for AIX... (0 Replies)
I have a korn shell script that executes a function which is stored in a common library. In the function there is obviously some code. Here is the line of code in the function in question:
temp=`echo $status_cnt|tr -d `
When the shell script executes with set -x, I'm seeing that on most... (2 Replies)
I am not able to run basic commands on my centos 7 server. The PATH variable looks correct I think. I have not seen this before and not sure what to do next. Thank you :).
# cd /usr/bin
# ls
bash: ls: command not found...
Similar command is: 'lz'
nano ~/.bashrc
bash: nano: command not... (6 Replies)
Discussion started by: cmccabe
6 Replies
LEARN ABOUT BSD
setbuffer
SETBUF(3S)SETBUF(3S)NAME
setbuf, setbuffer, setlinebuf - assign buffering to a stream
SYNOPSIS
#include <stdio.h>
setbuf(stream, buf)
FILE *stream;
char *buf;
setbuffer(stream, buf, size)
FILE *stream;
char *buf;
int size;
setlinebuf(stream)
FILE *stream;
DESCRIPTION
The three types of buffering available are unbuffered, block buffered, and line buffered. When an output stream is unbuffered, information
appears on the destination file or terminal as soon as written; when it is block buffered many characters are saved up and written as a
block; when it is line buffered characters are saved up until a newline is encountered or input is read from stdin. Fflush (see
fclose(3S)) may be used to force the block out early. Normally all files are block buffered. A buffer is obtained from malloc(3) upon the
first getc or putc(3S) on the file. If the standard stream stdout refers to a terminal it is line buffered. The standard stream stderr is
always unbuffered.
Setbuf is used after a stream has been opened but before it is read or written. The character array buf is used instead of an automati-
cally allocated buffer. If buf is the constant pointer NULL, input/output will be completely unbuffered. A manifest constant BUFSIZ tells
how big an array is needed:
char buf[BUFSIZ];
Setbuffer, an alternate form of setbuf, is used after a stream has been opened but before it is read or written. The character array buf
whose size is determined by the size argument is used instead of an automatically allocated buffer. If buf is the constant pointer NULL,
input/output will be completely unbuffered.
Setlinebuf is used to change stdout or stderr from block buffered or unbuffered to line buffered. Unlike setbuf and setbuffer it can be
used at any time that the file descriptor is active.
A file can be changed from unbuffered or line buffered to block buffered by using freopen (see fopen(3S)). A file can be changed from
block buffered or line buffered to unbuffered by using freopen followed by setbuf with a buffer argument of NULL.
SEE ALSO fopen(3S), getc(3S), putc(3S), malloc(3), fclose(3S), puts(3S), printf(3S), fread(3S)BUGS
The standard error stream should be line buffered by default.
The setbuffer and setlinebuf functions are not portable to non-4.2BSD versions of UNIX. On 4.2BSD and 4.3BSD systems, setbuf always uses a
suboptimal buffer size and should be avoided. Setbuffer is not usually needed as the default file I/O buffer sizes are optimal.
4th Berkeley Distribution May 12, 1986 SETBUF(3S)