So im having a bit of trouble here finishing up a program that involves the use of piping various unix commands in c. To be exact, I am struggling with how to make the redirect operator work.
Essentially the program it self will run a bunch of piped commands in c. For example you can give it the input:
ls -l | sort -n -r | head -n 3
and it should work as if you typed it into the terminal. My problem arises when I try to do:
ls -l | sort -n -r | head -n 3 > output.txt
My inital attempt was to search the string to see if the redirect operator existed. If so, then it would simply take some special branch where it could execute it, if not it would continue as if it did not exist. However my implementation to try this is shaky at best, so any explanation, help of what I should be doing would be greatly appreciated.
I have to:
pipe ls, tr, and cut to output the size (in bytes) and name of all of the files/dirs in the current directory (including any hidden ones), with the size at the beginning of the line, followed by a single tab character, followed by the the filename.
I don't know what the point of... (2 Replies)
I am using pipes (specifically piping out) in Perl to put an array from one file into an array in a different file. I can't figure out how to transfer the array. I kow how to open the pipe : open (FILEHANDLE, "| file") or die~
but how do I transfer the array. I think it has something to do with... (1 Reply)
Hi, I am trying to write a program that will pipe any number of programs together like in the linux shell. As an example, the below code tries to execute "cat data | grep int | cut -b 1-10." The problem is that the programs never get executed for some reason. It seems like the first program... (3 Replies)
All,
I am a UNIX novice with a question that I hope you can help me with.
I have a UNIX application called "Tole" that formats and displays specific information about customers. I can display the information for up to 30 customers by seperating customer IDs using commas in this format:
Tole -c... (3 Replies)
Is anyone piping commands to ex from scripts?
I.E. echo '%s/change this/to that/\nwq' | ex file.name
I've been using it for years with AIX, Solaris, SGI, with variations ksh and Mandriva and others with pdksh. I've just started using CentOS with ksh and it no longer works. I've tried single... (2 Replies)
I have a piping question, I am trying to implement piping on my own shell and am having some trouble...esentially I am trying to make something to do command|command|command.
I can get it to work fine if the last pipe command is not forked, but executes in the shell and then exits..but I need it... (2 Replies)
Hi All,
I am trying to perform the below csh code in Perl, but i am unfamiliar with Perl. Can anybody give me some advice on it ?
Csh Code:
cat filename |grep AAA| grep BBB| awk '{print("already_appended")' (11 Replies)
Hi,
I need to use a double grep so to speak. I need to grep for a particular item say BOB and then for each successful result I need to grep for another item say SMITH.
I tried grep "BOB" filename | grep "SMITH"
but it does not seem to work.
I can achieve my desired result using an... (12 Replies)
Hi everybody,
I have a big file with blast results (if you know what this means, otherwise look at it just as a text file with a specific form).
I am trying to extract some ids from within this file, which have certain parameters.
For example, some Of my IDs have the term 'No hit results'... (1 Reply)
Hi everybody,
I have a big file with blast results (if you know what this means, otherwise look at it just as a text file with a specific form).
I am trying to extract some ids from within this file, which have certain parameters.
For example, some Of my IDs have the term 'No hit results'... (6 Replies)
Discussion started by: frymor
6 Replies
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std::gslice_array
std::gslice_array< _Tp >(3) Library Functions Manual std::gslice_array< _Tp >(3)
NAME
std::gslice_array< _Tp > -
SYNOPSIS
Public Types
typedef _Tp value_type
Public Member Functions
gslice_array (const gslice_array &)
void operator%= (const valarray< _Tp > &) const
template<class _Dom > void operator%= (const _Expr< _Dom, _Tp > &) const
void operator&= (const valarray< _Tp > &) const
template<class _Dom > void operator&= (const _Expr< _Dom, _Tp > &) const
void operator*= (const valarray< _Tp > &) const
template<class _Dom > void operator*= (const _Expr< _Dom, _Tp > &) const
void operator+= (const valarray< _Tp > &) const
template<class _Dom > void operator+= (const _Expr< _Dom, _Tp > &) const
void operator-= (const valarray< _Tp > &) const
template<class _Dom > void operator-= (const _Expr< _Dom, _Tp > &) const
void operator/= (const valarray< _Tp > &) const
template<class _Dom > void operator/= (const _Expr< _Dom, _Tp > &) const
void operator<<= (const valarray< _Tp > &) const
template<class _Dom > void operator<<= (const _Expr< _Dom, _Tp > &) const
gslice_array & operator= (const gslice_array &)
void operator= (const valarray< _Tp > &) const
void operator= (const _Tp &) const
template<class _Dom > void operator= (const _Expr< _Dom, _Tp > &) const
void operator>>= (const valarray< _Tp > &) const
template<class _Dom > void operator>>= (const _Expr< _Dom, _Tp > &) const
void operator^= (const valarray< _Tp > &) const
template<class _Dom > void operator^= (const _Expr< _Dom, _Tp > &) const
void operator|= (const valarray< _Tp > &) const
template<class _Dom > void operator|= (const _Expr< _Dom, _Tp > &) const
Friends
class valarray< _Tp >
Detailed Description
template<class _Tp>class std::gslice_array< _Tp >
Reference to multi-dimensional subset of an array.
A gslice_array is a reference to the actual elements of an array specified by a gslice. The way to get a gslice_array is to call
operator[](gslice) on a valarray. The returned gslice_array then permits carrying operations out on the referenced subset of elements in
the original valarray. For example, operator+=(valarray) will add values to the subset of elements in the underlying valarray this
gslice_array refers to.
Parameters:
Tp Element type.
Definition at line 82 of file valarray.
Author
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libstdc++ Tue Jun 10 2014 std::gslice_array< _Tp >(3)